Marathon Monitors VersaPro Dew Point Dew Point Controller Installation and Operation Handbook

Marathon Monitors VersaPro Dew Point Dew Point Controller Installation and Operation Handbook
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Below you will find brief information for VersaPro Dew Point. The VersaPro is a single loop process controller / monitor that can be configured to perform a number of specific control functions. It includes features such as two channel 24 bit Sigma-Delta ADC, two form A alarm contacts, an internal relay for carbon sensor burnoff, an internal relay for sensor impedance testing, a serial EEPROM stores setup and calibration values, two 4-20 mA outputs for control or chart recorder, a sixteen character LCD with two four digit LED segment displays, an RS 485 serial communication port, two form A user configurable alarm contacts, and two form A control contacts (controller only).

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VersaPro Dew Point Controller Installation and Operation Handbook | Manualzz

VersaPro Dew Point

Controller/Monitor

Installation and Operation Handbook

MARATHON MONITORS, INC.

COPYRIGHT © 2008

Marathon Monitors Inc. Dew Point

Part # F200062

Revision 1.00 March 15, 2002

Revision 2.00 October 31, 2002

Revision 2.01 February 20, 2003

Revision 2.02 August 15, 2003

Revision 2.03 August 27, 2003

Revision 2.04 December 8, 2004

Revision 2.05 February 25, 2005

Revision 2.06 March 29, 2005 for Firmware Revision 1.11

Revision 2.07 September 2, 2005 for Firmware Revision 1.13

Revision 2.08 February 6, 2006 for Firmware Revision 1.15 and higher

Revision 2.09 July 19, 2006 for Firmware Revision 1.20 (2.20) and higher

Revision 2.10 April 19, 2007 for Firmware Revision 1.22 (2.22) and higher

Revision 2.11 Oct 7, 2008 for logo, address

COPYRIGHT © 2008

MARATHON MONITORS INC.

All trademarks used in this publication are duly marked and the sole property of their respective owners. No attempt at trademark or copyright infringement is intended or implied.

Modbus is a registered trademark of MODICON, INC.

Marathon Monitors makes no warranties express or implied beyond the written warranty presented at initial purchase. Marathon Monitors Inc. is not responsible for any product, process, damage or injury incurred while using this equipment. Marathon Monitors makes no representations or warranties with respect to the contents hereof and specifically disclaims any warranties of merchantability or fitness for any particular application or purpose.

For assistance please contact:

Marathon Monitors Inc.

TEL: +1 513 772 1000 • FAX: +1 513 326 7090

Toll-Free North America +1-800-547-1055 [email protected]

www.group-upc.com

Marathon Monitors Inc. Dew Point

Table of Contents

SAFETY AND ENVIRONMENT INFORMATION ........................................................................ 1

S

ERVICE AND REPAIR

......................................................................................................................... 1

INSTALLATION SAFETY REQUIREMENTS............................................................................... 1

S

AFETY

S

YMBOL

................................................................................................................................ 1

P

ERSONNEL

........................................................................................................................................ 1

E

NCLOSURE OF LIVE PARTS

................................................................................................................ 1

L

IVE SENSORS

.................................................................................................................................... 2

W

IRING

.............................................................................................................................................. 2

P

OWER

I

SOLATION

............................................................................................................................. 2

E

ARTH LEAKAGE CURRENT

................................................................................................................ 2

O

VER

C

URRENT PROTECTION

............................................................................................................. 2

V

OLTAGE RATING

.............................................................................................................................. 2

C

ONDUCTIVE POLLUTION

................................................................................................................... 3

O

VER

-

TEMPERATURE PROTECTION

..................................................................................................... 3

G

ROUNDING OF THE TEMPERATURE SENSOR SHIELD

.......................................................................... 4

I

NSTALLATION REQUIREMENTS FOR

EMC.......................................................................................... 4

R

OUTING OF WIRES

............................................................................................................................ 4

VERSAPRO FEATURES.................................................................................................................... 5

INSTALLATION ................................................................................................................................. 6

M

OUNTING

......................................................................................................................................... 7

PROCESS CONTROL OPTIONS ..................................................................................................... 7

CONTROL MODES............................................................................................................................ 8

T

IME

P

ROPORTIONING

(TP)................................................................................................................ 8

T

IME

P

ROPORTIONING

D

UAL

(TD)..................................................................................................... 9

T

IME

P

ROPORTIONING WITH

C

OMPLEMENT

(TC)............................................................................... 9

P

OSITION

P

ROPORTIONING

(PP) ......................................................................................................... 9

ON/OFF (OF) ................................................................................................................................... 9

ON/OFF D

UAL

(OD) ....................................................................................................................... 10

ON/OFF

WITH

C

OMPLEMENT

(OC) ................................................................................................. 10

D

IRECT

C

URRENT

O

UTPUT

............................................................................................................... 10

D

IRECT OR

R

EVERSE

C

ONTROL

A

CTION

.......................................................................................... 11

ANALOG OUTPUT CHANNELS.................................................................................................... 12

ALARMS ............................................................................................................................................ 13

P

ROCESS

A

LARMS

............................................................................................................................ 14

OFF ............................................................................................................................................ 15

Full Scale HI............................................................................................................................... 15

Full Scale LO.............................................................................................................................. 15

Deviation Band ........................................................................................................................... 15

Deviation High ........................................................................................................................... 15

Deviation Low............................................................................................................................. 15

Output High ................................................................................................................................ 15

Output Low ................................................................................................................................. 15

Fault ........................................................................................................................................... 15

Probe .......................................................................................................................................... 16

Marathon Monitors Inc. Dew Point

Time ............................................................................................................................................ 16

Start ............................................................................................................................................ 16

Soak ............................................................................................................................................ 16

A

LARM

A

CTION

............................................................................................................................... 16

A

LARM

D

ELAY

T

IMES

...................................................................................................................... 16

D

IAGNOSTIC

A

LARMS

...................................................................................................................... 17

SERIAL INTERFACE ...................................................................................................................... 18

FRONT PANEL OPERATION ........................................................................................................ 19

E

NTER

K

EY

...................................................................................................................................... 20

R

EMOTE

K

EY

................................................................................................................................... 20

S

ETPT

K

EY

....................................................................................................................................... 21

S

ETUP

K

EY

....................................................................................................................................... 21

D

UAL

K

EY

F

UNCTIONS

.................................................................................................................... 32

Starting Probe Tests ................................................................................................................... 32

Start Timer.................................................................................................................................. 32

Edit Timer................................................................................................................................... 32

Monitor Mode............................................................................................................................. 32

DIGITAL INPUT EVENT ................................................................................................................ 33

OFF ............................................................................................................................................ 33

PROB.......................................................................................................................................... 33

AUTO (controller only)............................................................................................................... 33

rEn (controller only).................................................................................................................. 33

ACK ............................................................................................................................................ 33

TIMER FUNCTION.......................................................................................................................... 35

S

ETTING THE

T

IMER

......................................................................................................................... 35

T

IME

................................................................................................................................................. 36

G

UARANTEED

S

TART

T

IMER

............................................................................................................ 36

G

UARANTEED

S

OAK

T

IMER

............................................................................................................. 37

T

IMER

A

LARM

B

EHAVIOR

................................................................................................................ 38

T

IMER

S

TATE

D

IAGRAM

................................................................................................................... 38

TIMER SIO OPERATIONS ............................................................................................................. 40

C

ONTROLLING THE

T

IMER

R

EMOTELY

............................................................................................. 41

PROBE IMPEDANCE TEST ........................................................................................................... 43

W

HY

M

EASURE

S

ENSOR

I

MPEDANCE

? ............................................................................................. 44

PROBE BURNOFF............................................................................................................................ 45

PROCEDURE TO TEST THE SENSOR ........................................................................................ 47

C

ORRECTLY SET UP THE PARAMETERS IN THE

V

ERSA

P

RO FOR THE

P

ROBE

T

ESTING

........................ 47

T

O MANUALLY START A PROBE TEST PROCEDURE

............................................................................ 47

I

F A

P

ROBE

F

AULT OCCURS

.............................................................................................................. 47

TUNING.............................................................................................................................................. 49

W

HAT IS TUNING

? ............................................................................................................................ 49

SCALING ANALOG INPUTS ......................................................................................................... 52

L

INEAR

A E

XAMPLE

......................................................................................................................... 52

SCALING ANALOG OUTPUTS ..................................................................................................... 53

Marathon Monitors Inc. Dew Point

CALIBRATION ................................................................................................................................. 54

C

ALIBRATION

D

ISPLAYS AND

K

EYBOARD

O

PERATION

.................................................................... 54

P

REPARING FOR

I

NPUT

C

ALIBRATION

.............................................................................................. 55

Calibration of the Thermocouple Input ...................................................................................... 55

Calibration of the Cold Junction Temperature........................................................................... 55

Calibration of the Probe Millivolt Input..................................................................................... 57

P

REPARING FOR

A

NALOG

O

UTPUT

C

ALIBRATION

............................................................................ 57

COMMUNICATIONS....................................................................................................................... 59

M

ODBUS

.......................................................................................................................................... 59

RTU Framing.............................................................................................................................. 59

Address Field.............................................................................................................................. 59

Function Field ............................................................................................................................ 60

Data Field................................................................................................................................... 60

Error Check Field (CRC) ........................................................................................................... 60

MMI M

ESSAGE

P

ROTOCOL

.............................................................................................................. 61

I

NSTRUMENT

T

YPE

‘U’ C

OMMAND

S

ET

........................................................................................... 64

‘X’ Command.............................................................................................................................. 64

Block Commands ........................................................................................................................ 66

MMI Error Codes ....................................................................................................................... 69

PROCESS CALCULATION ............................................................................................................ 70

D

EW

P

OINT

P

ROCESS

C

ONTROL

....................................................................................................... 70

TROUBLESHOOTING QUESTIONS ............................................................................................ 71

A

NALOG

I

NPUTS

............................................................................................................................... 71

C

ONTROL

O

UTPUTS

.......................................................................................................................... 71

D

IGITAL

C

OMMUNICATIONS

............................................................................................................. 72

D

ISPLAY

F

UNCTIONS

........................................................................................................................ 72

P

ROBE

C

ARE

.................................................................................................................................... 72

T

IMER

F

UNCTION

............................................................................................................................. 73

VERSAPRO MONITOR MODE...................................................................................................... 74

P

REPARE FOR

C

ONNECTION

............................................................................................................. 74

H

OW TO

C

ONNECT

........................................................................................................................... 74

S

TART

M

ONITOR

M

ODE

................................................................................................................... 75

‘D’ D

ISPLAY

C

OMMAND

.................................................................................................................. 76

‘L’ W

RITE

FLASH

TO

RAM D

EFAULTS

.......................................................................................... 77

‘K’ W

RITE

RAM

TO

EEPROM........................................................................................................ 77

‘J’ D

ISPLAY

EEPROM V

ALUES

....................................................................................................... 77

‘S’ S

TATUS

D

ISPLAY

........................................................................................................................ 77

‘W’ W

RITE

RAM

WITH

EEPROM

OR

D

ATA

V

ALUES

...................................................................... 77

‘X’ E

XIT

C

OMMAND

........................................................................................................................ 78

V

IEWING

S

TATUS AND

M

EMORY

...................................................................................................... 78

L

OADING

D

EFAULT

V

ALUES

............................................................................................................ 78

W

HAT IF AN ERROR OCCURS

............................................................................................................. 79

TECHNICAL SPECIFICATION..................................................................................................... 81

E

NVIRONMENTAL RATINGS

.............................................................................................................. 81

E

QUIPMENT RATINGS

....................................................................................................................... 81

G

ENERAL

......................................................................................................................................... 81

E

LECTRICAL SAFETY

(

PENDING APPROVAL

) ..................................................................................... 82

E

LECTROMAGNETIC

C

OMPATIBILITY

(

PENDING APPROVAL

) ............................................................ 83

VERSAPRO MEMORY MAP.......................................................................................................... 84

Marathon Monitors Inc.

Safety and Environment Information

Dew Point

Please read this section carefully before installing the controller

This instrument is intended for industrial applications used in conjunction with Marathon

Monitors zirconia carbon sensors and standard thermocouple types. It is assumed that any installation meets either CE standards for industrial safety or NEC standard wiring practices.

Failure to observe these standards or the installation instructions in this manual may degrade the safety or electrical noise protection provided by this instrument. It is the installer’s responsibility to ensure the safety and electrical noise compatibility of any installation.

Service and repair

This controller has user replaceable fuses but no other user serviceable parts. Contact your

Marathon Monitors Service (800-547-1055) for repair.

Caution: Charged capacitors

Before removing an instrument from its case, disconnect the supply and wait at least two minutes to allow capacitors to discharge. Failure to observe this precaution will expose capacitors that may be charged with hazardous voltages. In any case, avoid touching the exposed electronics of an instrument when withdrawing it from the case.

Electrostatic Discharge (ESD) Precautions

When the controller is removed from its case, some of the exposed electronic components are vulnerable to damage by electrostatic discharge. Anyone who is not probably ground using an ESD wrist strap or in contact with a ground while handling the controller may damage exposed electronic components.

Installation Safety Requirements

Safety Symbol

Various symbols are used on the instrument, they have the following meaning:

!

Caution, (refer to the accompanying documents)

Functional earth

(ground) terminal

The functional earth connection is required for safety ground add to ground RFI filters.

Personnel

Installation must be carried out by qualified personnel.

Enclosure of live parts

To prevent hands or metal tools touching parts that may be electrically live, the controller should be installed in an enclosure. The contacts on the rear of the instrument case or finger save but it is still possible for loose wiring, or metal objects to come in contact with live terminal connections. It is recommended that power be removed from the instrument connections before they are disconnected. However, instrument’s power connector can be

1

Marathon Monitors Inc. Dew Point

removed with power applied. Care should be taken that the connector does not come in contact with any grounded object.

Live sensors

The dc inputs, dc logic, and dc outputs are all electrically isolated from chassis ground. If the temperature sensor is connected directly to an electrical heating element then the inputs will also be live. The controller is designed to operate under these conditions. However you must ensure that this will not damage other equipment connected to these inputs and that service personnel do not touch connections to these terminals while they are live. With a live sensor, all cables, connectors and switches for connecting the sensor and non-isolated inputs and outputs must be mains rated.

Wiring

It is important to connect the controller in accordance with the wiring data given in this handbook. Take particular care not to connect AC supplies to the low voltage sensor input or other low level inputs and outputs. Only use copper conductors for connections (except thermocouple inputs) and ensure that the wiring for installations comply with all local wiring regulations. For example, in the UK, use the latest version of the wiring regulations,

BS7671. In the USA use NEC Class 1 wiring methods.

Power Isolation

The installation must include a power isolating switch or circuit breaker. This device should be in close proximity to the control actuator, and within easy reach of the operator. There is no means of disconnecting power from the instrument other than removing the connectors from the rear of the instrument. It is recommended that additional power disconnects are provided in the installation to remove power from these connectors as well.

Earth leakage current

Due to RFI Filtering there is an earth leakage current of less than 0.5mA. This may affect the design of an installation of multiple controllers protected by Residual Current Device,

(RCD) or Ground Fault Detector, (GFD) type circuit breakers.

Over Current protection

The instrument has an internal 3.15 Amp fuse (P/N MFU-3.15PCTT) for instrument power and 1 Amp fuses (P/N MFU-1.0PCTT) for the control contacts and alarms. It is recommended that additional protection against excess currents be used for loads exceeding this rating. Fusing and interposing relays should be added to the control circuit if high current or large inductive loads are used.

Voltage rating

The maximum continuous voltage applied between any of the following terminals must not exceed 250VAC:

• line or neutral to any other connection;

• relay output to logic, dc or sensor connections;

2

Marathon Monitors Inc.

• any connection to ground.

Dew Point

The controller should not be wired to a three phase supply with an unearthed star connection.

Under fault conditions in this supply could rise above 264VAC with respect to ground and the product would not be safe.

Voltage transients across the power supply connections, and between the power supply and ground, must not exceed 2.5kV. Where occasional voltage transients over 2.5kV are expected or measured, the power installation to both the instrument supply and load circuits should include a transient limiting device.

These units will typically include gas discharge tubes, metal oxide varistors, and constant voltage transformers help suppress voltage transients on the supply line due to lightning strikes or inductive load switching. Devices are available in a range of energy ratings and should be selected to suit conditions at the installation.

Conductive pollution

Electrically conductive pollution must be excluded from the cabinet in which the controller is mounted. For example, carbon dust is a form of electrically conductive pollution. To secure a suitable atmosphere in conditions of conductive pollution, fit an air filter to the air intake of the cabinet. Where condensation is likely, for example at low temperatures, include a thermostatically controlled heater in the cabinet.

Over-temperature protection

When designing any control system it is essential to consider what will happen if any part of the system should fail. In temperature control applications the primary danger is that the heating will remain constantly on. Apart from scrapping the product, this could damage any process machinery being controlled, or even cause a fire.

Reasons why the heating might remain constantly on include:

• the temperature sensor becoming detached from the process;

• thermocouple wiring becoming a short circuit;

• the controller failing with its heating output constantly on;

• an external valve or contactor sticking in the heating condition;

• the controller setpoint set too high.

Where damage or injury is possible, we recommend fitting a separate over-temperature protection unit. Factory Mutual requires that any over temperature device use an independent temperature sensor, which will isolate the heating circuit.

Please note that the alarm relays within the controller will not give protection under all failure conditions. This instrument is not suited for over temperature protection and should not be used as a safety device.

3

Marathon Monitors Inc. Dew Point

Grounding of the temperature sensor shield

In some installations it is common practice to replace the temperature sensor while the controller is still powered up. Under these conditions, as additional protection against electric shock, we recommend that the shield of the temperature sensor be grounded at one end of the wire. Do not rely on grounding through the framework of the machine.

Installation requirements for EMC

To ensure compliance with European EMC directives certain installation precautions are necessary as follows:

• When using relay outputs it may be necessary to fit a filter suitable for suppressing the emissions. The filter requirements will depend on the type of load. For typical applications such as Schaffner FN321 or FN612 line filters or equivalents.

• If the unit is used in table top equipment which is plugged into a standard power socket, it is likely that compliance to the commercial and light industrial emissions standard is required. In this case, to meet the conducted emissions requirement, a suitable mains filter should be installed. Recommended filters would be Schaffner types FN321 and

FN612 or equivalents.

Routing of wires

To minimize the pick-up of electrical noise, the wiring for low voltage dc and particularly the sensor input should be routed away from high-current power cables. Where it is impractical to do this, use shielded cables with the shield grounded at one end.

4

Marathon Monitors Inc.

VersaPro Features

Dew Point

The VersaPro is a single loop process controller / monitor has the following capabilities:

Both Controller and Monitor

• Two channel 24 bit Sigma-Delta ADC for thermocouple, probe millivolt, with cold junction compensation.

• Two (2) Form A alarm contacts.

• Internal relay for carbon sensor burnoff.

• Internal relay for sensor impedance testing.

• Serial EEPROM stores setup and calibration values.

• Two (2) 4-20 milliamp outputs for control or chart recorder.

• Sixteen character LCD with two four digit LED segment displays.

• RS 485 serial communication port for either MMI protocol or Modus.

• Two (2) Form A user configurable alarm contacts.

Controller only

• Two (2) Form A control contacts.

• PID control mode.

5

Marathon Monitors Inc.

Installation

Dew Point

The VersaPro instrument is designed for up to 1/8" panel mounting in a DIN standard opening of 3.62" square (adapter panels available by special order). Required rear clearance is 7” to allow for wiring.

As with all solid state equipment, the controller should be located away from excessive heat, humidity, and vibration. Since the unit uses LED and LCD display devices, it should also be located so that direct sunlight will not interfere with the display's visibility. The instrument requires 120/240 VAC 50/60 Hz and should not be on the same circuit with other noise-producing equipment such as induction machines, large electrical motors, etc. Signal wiring must be run separate from control wiring. It is suggested that signal wiring at the rear terminals of the instrument be routed in one direction (up or down) while the AC power wires are routed in the opposite direction.

The following figure shows the rear terminals locations on the rear of the VersaPro.

Figure 1 VersaPro Rear Panel

The next figure shows a typical wire schematic for the Versapro Dew Point controller.

6

Marathon Monitors Inc. Dew Point

Figure 2 Typical Wiring Schematic

Mounting

To mount the instrument in a control panel, a hole must be cut 3.62" square in the necessary location on the panel. The following procedure should be followed to mount the VersaPro in the panel.

1) Insert the unit into previously cut out 3.62" square hole in panel.

2) While supporting unit, insert one clamping bracket into the groove on the bottom of unit, and then install the 6-32 set screw.

3)

4)

Repeat step 2 for the top of the unit.

With a HEX KEY wrench, alternately tighten the screw on either side of instrument to a torque of six in.-lbs. Insure rigidity of mounting. DO NOT OVER TIGHTEN.

This can wrap the instrument enclosure and make removal difficult.

To remove the instrument from the panel, reverse the above procedures.

Process Control Options

7

Marathon Monitors Inc. Dew Point

The Versapro can be configured to perform a number of specific control functions. The following table outlines the available process functions for the dew point controller / monitor.

Table 1 Instrument Control Options

Function

Dew Point

Linear Input A

Linear Input B

Description

Uses the millivolt and temperature signals from a zirconia sensor to calculate Dew

Point concentrations and control to an Dew

Point set point.

Uses the millivolt signal from a linear sensor connected to terminals +TC / -TC

Uses the millivolt signal from a linear sensor connected to terminals +MV / -MV

Control Modes

The VersaPro controller provides:

• Time Proportional Single (TP)

• Time Proportional Dual (TD)

• Time Proportional Compliment (TC)

• Position Proportioning (PP)

• On/Off (OF)

• On/Off Dual (OD)

• On/Off Compliment (OC)

• Direct Signal Output (4-20mA)

The instrument controls with two control contacts or direct 4-20mA output from two analog output channels. The control function can be set to direct acting or reverse acting.

Direct acting increases the output control signal to increase the process. Reverse acting decreases the output control signal to increase the process.

Time Proportioning (TP)

Time proportioning adjusts the duty cycle of the control device to maintain control. This is usually done with solenoid valves controlling the flow of a trim gas or addition to the process. The control loop percent output is the ON time percentage of the value relative to total cycle time. The cycle time is the ON time plus OFF time.

For example if the control loop percent output is 34% and the cycle time is 10 seconds, then the ON time would be 3.4 seconds and the OFF time would be 6.6 seconds. The selection of the proper cycle time is a trade off between excess wear and tear on the solenoid valve with short cycle times and rough (pulsing) flow of the control material with long cycle times.

Only the first control contact is used in this mode.

8

Marathon Monitors Inc. Dew Point

Time Proportioning Dual (TD)

This mode is used when there are two processes to control that have complementary effects; like gas and air. The time proportioning dual mode uses two control outputs; one for gas and one for air. There is never a time when both outputs are on simultaneously. The control loop computes a percent output from -100 to +100%. When positive, the proportioning action applies to the forward output (gas). When negative the proportioning action applies to the reverse (air) output.

Time Proportioning with Complement (TC)

This mode is identical to the time proportioning mode except that both control outputs are used. The second control output is the complement of the first. That is when the first output is ON then the second is OFF and vice versa. This mode is used with single action motorized valves that open quickly when a voltage is applied to one terminal and close quickly when voltage is applied to the other terminal.

Position Proportioning (PP)

This mode is used with motorized valves that do not have slidewire feedback. This mode is sometimes referred to as the "bump" mode because it "bumps" the valve slightly more open or closed. This mode uses both control outputs; one to drive the motor forward (open) and the other to drive it reverse (closed). The control output is the difference between the new percent output and the last percent output. If the difference is positive than the valve motor is driven open for that percentage of the cycle. If negative it is driven closed by that percentage of the cycle time.

For example if the new percent out is 60% and the old was 45% then the motor is driven open for 15% of the cycle time. If the cycle time is set to the time that the motor takes to move from fully closed to fully open, then the flow is theoretically increased by 15%. Two special cases exist. If the control output is computed at 100% then the motor is driven continuously in the open direction. Likewise if the control output is computed as 0% then the motor is driven continuously closed.

There is a built in deadband for this control based on the length of the cycle time. The comparison between the previous and current output values are made at the end of each cycle time. Faster comparisons can be made by shortening the cycle time assuming that a

100% command output is a continuously closed control contact.

ON/OFF (OF)

ON/OFF control is exactly what it implies, the control action is either ON or OFF. With true

ON/OFF control the control output is ON whenever the process is below the setpoint value and OFF when the process is at or above the process value. In many real world applications this simple control method will cause "contact chatter" because of noisy signals which will switch the ON and OFF states rapidly. Also since the control action does not turn OFF until the setpoint is reached, the process will overshoot due to lags in the control action.

Marathon controllers incorporate two features that prevent these problems from occurring; hysteresis and deadband. Hysteresis provides a delay between the control on point and the

9

Marathon Monitors Inc. Dew Point

off point. Noise will not cause the control output to “chatter” with this gap applied.

Hysteresis is ±20% of the deadband value.

Deadband allows the process to deviate away from the setpoint by the width of the deadband before any control action occurs. The deadband is adjusted through the Proportional Band in units of the displayed setpoint value. The reset and rate values have no effect in ON/OFF control.

Let’s assume the process setpoint is 50° dew point with a proportional band of 5. This represents a deadband of 5°, which is a band of ±5° dew point around setpoint. The hysteresis is 1° of the setpoint or 20% of the deadband. The output is turned on when the process drops below 45° and turns off then it reaches 49°.

ON/OFF Dual (OD)

This mode is similar to the time proportioning dual mode. The forward output acts as described in the ON/OFF description above. The reverse output responds when the process is above the setpoint.

Using the dew point example with a proportional band (deadband) of 5, the gas contact would turns on when the process is 45° and will turn off when it comes to 49°. Likewise the air contact would turn on when the process exceeds 55° and will turn off when it drops to

51°.

ON/OFF with Complement (OC)

This mode is exactly like ON/OFF control with the addition of a second control output. The second control contact is turned ON when the first is control contact is OFF and vice versa.

Direct Current Output

The Versapro has two analog output channels that provide an isolated 4 to 20mA signal proportional to selectable process values. The analog outputs can be configured to control the process by driving actuators with a 4-20mA signal proportional to the calculated percent output of the PID loop. One or both output channels can be used depending on the control mode selected. POUT selection drives the output signal based on the HIPO and LOPO settings. If a Dual Time Proportioning control mode is selected with a HIPO = 100 and a

LOPO = -100 then the output will be 4mA for –100%, 12mA for 0%, and 20mA for +100% output. This setting is helpful if one actuator is driving two valves in a split configuration where air is fully opened at –100% and gas is fully opened at +100% or both are closed at

0%.

It is possible to drive two actuators independently by setting on output to PO1 or PO2 where

PO1 is the 0 to +100% control output and PO2 is 0 to –100%. In this configuration both outputs are at the maximum (±100%) with an output of 20mA.

It is also possible to drive one actuator with an output channel and a solenoid with a control contact. For example, select PO1 for one analog output channel to drive a gas actuator and connect an air solenoid to the reverse control contact. The percent output for both functions

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Marathon Monitors Inc. Dew Point

is determined by the PID settings. The cycle time should be set to the stroke time required to fully open the actuator from a fully closed condition. Typical stroke times would be 30 to 45 seconds.

Direct or Reverse Control Action

Control action determines how the output of the controller will react to effect a change on the process. The control action is considered ‘direct’ if an increase in the output produces an increase in the process value. A ‘reverse’ control action would be when an increase in the output produces a decrease in the process.

For example oxygen would require a reverse acting control if the process component the instrument is controlling is a trim gas. Increasing the trim gas will result in a decrease in the oxygen reading. It would be considered a direct acting control if the process component under control is additional air. Either process would use the first control contact, it would just be activated above or below the process set point depending on what is being added to the process.

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Analog Output Channels

Dew Point

The two analog output channels can also be set to retransmit selectable process values. The

Analog Output Offset and Range can be set to correspond to the process range. The default settings for these channels is –99.9° – 212.0° for channel 1 and 0 to 2000° temperature for channel 2.

The Versapro output channels can drive a chart recorder or PLC input. The remote input should be configured for of 0 - 5 VDC or 4 - 20 mA. If the input device only responds to a

DC voltage input, it will be necessary to add a 250 ohm dropping resistor across its input terminals and scale the analog output as 0 – 20mA.

The ideal location of the input device such as a recorder is adjacent to the instrument but it may be located remotely if the connecting wires are properly shielded. For best results, the chart recorder input(s) should be isolated from ground with the cable shield grounded on one end of the cable.

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Alarms

Dew Point

The instrument has two types of alarms, process alarms and diagnostic alarms. If an alarm has been selected and conditions are such that the alarm becomes active, the instrument will display this condition on the center LCD display. Alarms can be configured as latched or non-latched and as direct or reverse.

A reverse configuration would be considered a failsafe setting since the alarm contact is closed during normal conditions and opens if power is removed to the instrument or the configured alarm condition occurs.

The alarm message will be displayed on the LCD screen with it occurs. If the LCD screen is written with another message all active alarms can be seen be pressing the up or down arrow keys.

The display can not be cycled to other parameters such as temperature or probe millivolts if an alarm is active.

ALARM DISPLAY CONDITION

HIGH ALARM Alarm contact assigned to FSHI, dUbd, bdHI,

HIPO

LOW ALARM

PROBE CARE

FAULT

TIMER END

LLLL

HHHH

Alarm contact assigned to FSLO, dUbd, bdLO,

LOPO

Alarm contact assigned to PrOb

Alarm contact assigned to TinE, Strt, SOAK

Display only

Display only

ACTION

Full Scale High, above

Deviation Band, or above percent output setting. Contact automatically resets unless latched.

Full Scale Low or below

Deviation Band, or below percent output setting. Contact automatically resets unless latched.

Probe impedance high or probe recovery time exceeds limit. Contact resets monetarily unless latched.

Timer end alarm when the timer counts to zero for Timer, Start, or Soak timer modes. The contact latches until reset by pressing the

Enter key or through the

Input Event.

Displays process value is negative and exceeds display range or exponent setting

Displays process value is

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FLASH CSUM Alarm contact assigned

FALt

EEPROM CSUM Alarm contact assigned

FALt positive and exceeds display range or exponent setting

Reset instrument power.

Return to Marathon if error does not clear.

Reset instrument power.

Return to Marathon if error does not clear.

Dew Point

FLASH ERASE

FLASH / EE SIZE

ADC FAULT

TEMP OPEN

FALt

Alarm contact assigned

FALt

Alarm contact assigned

FALt

Alarm contact assigned

FALt

Alarm contact assigned

FALt

Do not push any keys while instrument is powered on. Return to

Marathon if error does not clear.

Programming error,

Reset instrument power, attempt reload.

Programming error,

Reset instrument power, attempt reload.

Reset instrument power.

Return to Marathon if error does not clear.

Check thermocouple for open condition or loose connection.

MV OPEN

CPU FAULT

Alarm contact assigned

FALt

Alarm contact assigned

FALt

Check probe millivolt signal for open condition or loose connection.

This signal can only be tested if the probe temperature is above

1300°F and exposed to process gas.

Reset instrument power.

Return to Marathon if error does not clear.

CPU IDLE ZERO Alarm contact assigned

FALt

Idle timer of CPU has counted to zero. This means that a CPU process has exceeded an allocated time slot.

Possible during extended block transfer requests.

Process Alarms

The process alarms can be setup to activate either or both of the two alarm contacts provide on the VersaPro. Nine user selectable modes are available.

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OFF

Disables the alarm function and the alarm contacts.

Dew Point

Full Scale HI

An alarm is generated any time the process value goes above the Full Scale HI alarm value. This alarm is reset if the process falls below the alarm value or acknowledgement from the front panel or through the event input (if configured).

Full Scale LO

An alarm is generated any time the process value drops below the Full Scale LO alarm value. The alarm will arm once the process is measured above the alarm value. This alarm is reset with an acknowledgement from the front panel or through the event input

(if configured).

Deviation Band

An alarm is generated any time the process value goes above or below the band alarm setting. The alarm setting is

± value of the band. For example, if a value of 10 is entered as the alarm value, an alarm is generated if the process goes 10 units above or

10 units below the set point. Units are the process units such percent or degrees. This alarm will not arm until the process is in-band of the set point.

Deviation High

An alarm is generated any time the process value goes above the band alarm setting.

The alarm setting is number of units allowed above set point. Units are the process units such percent or degrees. This alarm will not arm until the process is in-band of the set point.

Deviation Low

An alarm is generated any time the process value goes below the band alarm setting.

The alarm setting is number of units allowed below the set point. Units are the process units such percent carbon or degrees. This alarm will not arm until the process is inband of the set point.

Output High

An alarm is generated any time the control percent output exceeds the alarm value. The alarm setting is maximum percent output allowed.

Output Low

An alarm is generated any time the control percent output drops below the alarm value.

The alarm setting is minimum percent output allowed.

Fault

An alarm is generated any time an open input occurs on either the T/C or MV inputs.

Both inputs are pull up to a maximum value if no input is connected or if the input fails in an open circuit mode. An open T/C input fault is ignored for the Linear configuration. The center display will indicate which of these conditions has caused the alarm. The alarm process will also become active if any of the listed hardware faults occur. The center display will indicate which of these conditions has caused the alarm.

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Probe

An alarm is generated any time the probe exceeds the maximum probe impedance setting, or the verification test tolerance. All of the probe values and limits are configured in the Probe Menu. The center display will indicate which of these conditions has caused the alarm.

Time

This alarm setting is necessary for the timer function to work. The timer will only run if it is enabled in the Ctrl Setup menu and a timer setpoint value other than zero has been assigned. This alarm setting allows the timer to start running when it is activated at the Start Timer parameter in the Setpt key menu, when the dual key combination Left

Arrow and Enter keys are pressed, or if the Input Event has been configured for Start and a contact closure occurs. The timer will start running as soon as it starts, independent of any process values. See the Timer section for more details.

Start

This alarm setting is necessary for the timer function to work. The timer will only run if it is enabled in the Ctrl Setup menu and a timer setpoint value other than zero has been assigned. This alarm setting allows the timer to be activated from the Start Timer parameter in the Setpt key menu, when the dual key combination Left Arrow and Enter keys are pressed, or if the Input Event has been configured for Start and a contact closure occurs. The timer will start running as soon as the process level is above the alarm value and will continue to run once it has started. See the Timer section for more details.

Soak

This alarm setting is necessary for the timer function to work. The timer will only run if it is enabled in the Ctrl Setup menu and a timer setpoint value other than zero has been assigned. This alarm setting allows the timer to be activated from the Start Timer parameter in the Setpt key menu, when the dual key combination Left Arrow and Enter keys are pressed, or if the Input Event has been configured for Start and a contact closure occurs. The timer will start running as soon as the process level is with in the band around set point determined by the alarm value. The timer will stop any time the process falls outside the band limit. See the Timer section for more details.

Alarm Action

Each alarm can be configured to operate in several different modes. Each alarm can be configured as a reverse (normally closed) contact. This mode is usually used for failsafe alarms that will open during an alarm condition, fault, or power failure. Each alarm can also be configured as a direct (normally open) contact that closes when an alarm condition occurs. In both cases the alarm will automatically clear if the alarm condition is resolved.

Each alarm can also be configured for either reverse or direct latched conditions. In this mode the alarm contact will remain active until an acknowledgement is received through the configured Event Input terminals or by pressing the ENTER key.

Alarm Delay Times

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Each alarm can have delay ON, delay OFF, or both delays applied. Delays can be applied in increments of a second, up to a maximum of 250 seconds. ON delays are helpful if a known upset in the process can be ignored. This avoids nuisance alarms but still maintains an active alarm if the alarm condition persists following the delay. OFF delays will hold the alarm contact active for a determined period of time once the alarm condition has cleared. This can be helpful as an interlock to other process functions that may have to recover following an alarm condition.

Diagnostic Alarms

A diagnostic alarm is shown on the instrument’s center display when a fault is detected in the internal hardware during power up. These alarms included:

FLASH CSUM FAULT A fault has been detected in the Flash memory.

EEPROM CSUM FAULT A fault has been detected in the EEPROM.

KEYBOARD FAULT A key is stuck or was held down during power up.

FLSH ERASE FAULT This error may occur during instrument programming.

The Flash memory may be faulty. Retry programming, make sure the communications link to the instrument is working properly.

FLSH SIZE FAULT This error may occur during instrument programming. The

Flash memory may be faulty. Retry programming, make sure the communications link to the instrument is working properly.

ADC FAULT The analog / digital converter has failed to initialize or failed self calibration.

CPU IDLE ZERO A CPU process has exceeded the allotted process time.

Maybe due to extended serial communications block transfers. Limit the number of parameters requested in a block in this condition occurs.

CPU FAULT Occurs if the CPU has not initialized correctly. Try resetting power.

If either alarm contact is configured for a fault this alarm will engage if any of the above faults occur. The LCD display will indicate the fault condition.

The front panel display will show LLLL if the process value is below the display resolution, or HHHH if the process value is above the display resolution. It may be necessary to adjust the decimal point settings if these symbols occur.

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Serial Interface

Dew Point

The VersaPro has a single RS-485 half duplex (two wire) communications port. This port can be configured for either the Marathon protocol of Modbus RTU protocol. Baud rates and parities are selectable. The Modbus protocol only uses a parity of none. See the section on communications for details on both of these protocols.

The Versapro can be connected to networks with up to 128 similar devices. The differential transceiver used in the Versapro meets or exceeds the TIA/EIA-485 and ISO/IEC

8482:1993(E) standards.

Connections for the serial interface should be connected to the following terminals:

TB-B 13

TB-B 14

RTX +

RTX –

All connections to any RS-485 bus should be made with shielded twisted pair wires using a low capacitance cable specified for RS-485 multi-drop connections. The shield should be connected to ground on one end of the wire run. Shield continuity should be maintained between wire segments. Each end of the network should be terminated with a resistor that is close to the impedance of the cable. 100 to 120 ohms are typical values. All connections to multiple instruments should be made in a daisy-chain fashion, from one instrument to the next. A star network connection should never be used. A repeater should be considered for cable distances beyond 3900 feet (1.2Km). Any network that is run between buildings should use repeaters with optical fiber connections between buildings to avoid any noise spikes generated by lightening strikes.

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Front Panel Operation

Dew Point

The instrument has a display/keyboard assembly. This assembly has a 2 x 4 keyboard group, two groups of four LED seven segment displays (upper and lower), and a single line sixteen character LCD display.

45.0

1753

Figure 3 Versapro Display

The LEDS to either side of the LED segment arrays light when the corresponding function is active.

• COMM flashes when the instrument is properly interrogated over the RS485 port.

• PWR is hard wired to the instrument 5VDC supply

• AUTO is lit when the instrument is controlling to a set point (controller option)

• REM is lit when the instrument is controlling to a remote set point (controller option)

• REM and AUTO flash together if the instrument is in manual mode.

• REM will flash if timer is running.

The upper display indicates the process value or the Setup Menu Heading when the SETUP key has been pressed.

The center display indicates what the measured process calculation is and what the lower display indicates. In figure 3 the instrument is indicating dew point that is being measured.

This measurement range is –99.9° to 212.0°. The lower display can show a number of parameters depending on how many times the Enter key is pressed. The default low display is set point.

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Marathon Monitors Inc. Dew Point

The center display also shows the parameter name in Setup mode or fault and alarm messages if any are active.

The lower display shows the instrument set point if the controller is in automatic or remote mode. The display will switch to control output level when the instrument is changed to manual. The lower display can also be configured to show the probe temperature

Enter Key

If the normal process display is showing on the LED and LCD displays, then pressing the

Enter key will cycle the LCD and lower LED through various controller parameters. The display will cycle through

DEWPT / SETPT

DEWPT / TEMP

DEWPT / %OUT

PROBE MILLIVOLT

BOFF MILLIVOLT

PROBE IMPEDANCE

PROBE IMP RECOVERY

NEXT PROBE TEST

REMAINING TIME

The dew point process value will always be displayed in the top LED display. The display can not be cycled if there is an active alarm. If the alarm is not displayed on the LCD screen then the UP or DOWN arrow keys can be pressed to display all of the active alarms.

Remote Key

Pressing the REM key causes the VersaPro to cycle between Remote, Automatic, or Manual control. This key has no function in the monitor version. When switching from Automatic to Manual or Manual to Automatic, the control output remains at the last output value in either mode. This allows for a bumpless control transition between either mode.

When the controller is set to Automatic mode the “Auto” LED lights and the lower display indicates the process setpoint (default).

When the controller is set to Remote mode the “Rem” LED lights and the VersaPro will accept a remote setpoint from a master on the host serial interface. The lower display indicates the process setpoint (default). The Setpt key does not work if the instrument is in remote mode.

When the controller is set to Manual mode both the “Rem” and “Auto” LED’s will flash together and the lower display indicates the power output of the controller. This value can be manually increased or decreased in 1% steps by pressing the UP or DOWN arrow keys.

Pressing the RIGHT or LEFT arrow keys changes the output in 10% steps. The output will remain in the last control level if the instrument is switched into manual mode from remote or automatic or back to either setpoint control mode.

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Setpt Key

The Setpt key provides access to the instrument process set point. When the key is pressed the center display will show “SET POINT”. The set point value in the lower display can then be manually changed by moving the flashing digit cursor with the RIGHT or LEFT arrow keys and increasing or decreasing the selected digit with the UP or DOWN arrow keys. You can exit the set point function by pressing the Setpt key again. Any changes that are made to the set point are then displayed in the lower window if the instrument is set up of

Automatic control.

The following table outlines the options available under the Set Point key.

Table 2 Setpoint Ranges

Parameter Name

SET POINT

TIMER SETPOINT

START TIMER

Range

0 – 2.55% DEWPT

-999 – 9999

0 – 9999

YES / NO

Description

Units for DEWPT or linear input.

Units in minutes

Starts timer when YES is selected. This is the same as pressing the dual keys LEFT arrow and Enter to start the timer.

Setup Key

The instrument can be placed in setup mode by pressing and holding the SETUP key for 5 seconds. The upper display initially shows the first setup menu while the center and lower displays are blank. At this level you can select different menus by pressing the RIGHT or

LEFT arrow keys. The upper display will change accordingly.

You can enter a menu by pressing the ENTER key when the desired menu heading is being displayed. Pressing the arrow keys will change menu parameters. Value changes can be saved or the next parameter can be selected by pressing the ENTER key. The menu parameters will continue to cycle through the display as long as the ENTER key is pressed.

A new menu can be select only when the menu heading is displayed. You can exit from the

Setup mode by pressing the SETUP key at any time.

The following tables outline the Setup menus available in the VersaPro Controller and

Monitor when the operator presses the SETUP key.

Table 3 Setup Menus

Setup Menu Heading

CtrL

Inpt

CaLc

Prob

Description

Control functions and PID

Thermocouple type and Millivolt setup

DEWPT process values

Probe tests and verification parameters

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Aout

ALr

Host

Info

CaL

Analog output selection and parameters

Alarm contact configurations

Communication protocols and parameters

General information displays

Input / Output calibration

Dew Point

You have to press the SETUP key for five seconds to activate the setup mode. Initially when the setup mode is activated, the upper LED display will show the first menu heading, the LCD and lower LED displays are blank. Page to the next Menu heading by pressing the

RIGHT or LEFT arrow keys. The menu headings will continue to wrap around as the

RIGHT or LEFT arrow keys are pressed. Pressing the SETUP key at any point while in the

Setup Menus will return the display to the normal process display.

Ct r L dPT

The displayed menu is selected by pressing the ENTER key. The first parameter name in the selected menu list will appear in the center display. The upper LED group continues to display the menu name, and the lower LED group shows the parameter value. A flashing cursor in the lower LED display indicates which digit can change if the parameter value is numeric. The UP or

DOWN arrows increase or decrease the digit value. The RIGHT or LEFT arrow keys move the cursor to the right or left digit. Numeric wrap-around is provided as well as wrap-around for the menu parameters. No wrap-around is provided for the cursor position when changing a parameter value.

If the parameter has a table of choices such as thermocouple types, the various selections can be displayed by pressing the UP or DOWN arrows. No digit flashes in parameters that have a list selection. In either case, the selection is set when the ENTER key is pressed and the display advances to the next parameter.

In the example shown above, the selected menu is Control (CtrL), the selected parameter is

Process Source, and the selected source is DEWPT. Different source selections can be made by pressing the UP or DOWN arrow keys.

Pressing the SETUP key at any time escapes from the menu display and returns to the normal process display. You can only select another menu heading when the display is at a menu heading.

The following figures and tables outline the menu options and parameters under the Setup key.

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Figure 4 Setup Menu Tree

Dew Point

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Table 4 Control Menu (

CtrL)

Dew Point

Parameter Name

PROCESS SOURCE

TC OR MV BREAK

Units or Options Range

DEWPT, E A,

E B

Display range:

00.00 to 02.55 for DEWPT

-999 to 9999 for

Input A or Input B

ZERO,

HOLD

Description

Control type only available on instrument’s specific configuration. This selection controls what other parameters will be available. E A is input

A (0-50mV), E B is input B (0-

2000mV)

ZERO sets the control output to

0 if a thermocouple break and/or an open mV input are detected. HOLD holds the output and the last process value prior to an opened input.

HOLD will take effect temporarily if the mV signal changes by more then 50mV between samples. This prevents changes if the mV signal is failing.

The following parameters in this table are only available in the controller

CONTROL MODE

CONTROL ACTION

PROPORTIONAL

BAND

RESET

RATE

CYCLE TIME

TP, TC, TD, PP,

OF, OC, OD or

NON

DIR/REV

Process Value repeats/min

Minutes

SECONDS

HI PERCENT OUT MAXIMUM

OUTPUT

LOW PERCENT OUT MINIMUM

OUTPUT

TIMER ENABLE YES / NO

0 – 9999

00.00 – 99.99

00.00 – 9.99

0 – 250

0 – 100

-100 to 100

See Control Modes if configured as a controller, shows NON (MONITOR) only if the instrument is configured as a monitor.

Direct or Reverse control action

Proportional Band value in displayed process units for PID control or Deadband in

ON/OFF control

Integral control value, no effect in ON/OFF settings

Derivative control value, no effect in ON/OFF settings

Proportional time period (TP,

TC, TD)

Motor cycle time (PP)

Minimum ON time

(OF,OC,OD)

Sets max. forward control.

Output

Sets min. reverse control output

Enables timer function

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Table 5 Input Menu (

InPt)

Parameter Name

TC TYPE

Units or Options Range

B, E, J, K, N, R, S,

T

COLD JUNC APPLY YES or NO

IN A OFFSET

IN A SLOPE

TEMP SCALE

TC FILTER

IN B OFFSET

IN B SLOPE

MV FILTER

Only in Linear mode

Only in Linear mode

F OR C

-999 – 9999

-999 – 999

-99.9 – 99.9

-9.99 – 9.99

-.999 - .999

0 – 450

Works only in mV

Mode

-999 – 9999

Works only in mV

Mode

-999 – 999

-99.9 – 99.9

-9.99 – 9.99

-.999 - .999

0 – 450

Dew Point

Description

See Input calibration for thermocouple ranges.

Linear mode allows for input scaling, see IN A OFFSET and IN A SLOPE.

Applies the cold junction correction or not when a thermocouple type is selected.

In LINEAR mode the cold junction is never applied.

Default is NO.

Linear offset to scale Input A to Engineering Units when

INPUT A is selected as the process source.

Linear slope to scale Input A to Engineering Units when

INPUT A is selected as the process source.

This is the slope number in the linear calculation where:

EU = SLOPE(mV) +

OFFSET

See key

Sets temperature scale.

Temperature filter setting in seconds. Filters the temperature value with a moving average time window.

Linear offset to scale Input B to Engineering Units when

INPUT B is selected at the process source. This is the offset in used in the

SLOPE(mV) + OFFSET equation.

Linear slope to scale Input B to Engineering Units when

INPUT B is selected as the process source.

This is the slope number in the linear calculation where:

EU = SLOPE(mV) +

OFFSET

Millivolt filter setting in seconds. Filters the millivolt

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Parameter Name Units or Options Range

Dew Point

DIG EVENT OFF, PrOb,

AUtO, rEn, ACK,

PrOC, Strt, HOLd,

End

Description reading with a moving average time window.

See Digital Event section for an explanation of selections.

See the Timer section for the

Strt, HOLd, and End selections.

Table 6 Calculation Menu (

CALC)

Parameter Name Units or Options Range

DISPLAY DECML PT Decimal point 0-4

DEWPT PROCESS

FACTOR

0 – 1999

Description

Sets decimal pt., for Input A and Input B. DEWPT defaults to 2.

Used to correct displayed

DEWPT value when compared to shim stock readings.

Table 7 Probe Setup Menu (

PrOb)

Parameter Name

PROBE TEST

START TEST

TEST INTERVAL

PROBE IMP LIMIT

IMP RECVRY

TIME

BURNOFF DELAY

Units or Options Range

NONE

RES

BOFF

BOTH

HRS.TENTHS

KOHMS

SECONDS

SECONDS

YES/NO

0 – 99.9

10 – 100

0 – 250

0 – 999

Description

No test (NONE),

Impedance (RES), Burnoff

(BOFF), or BOTH impedance and burnoff can be selected.

If probe test interval is 0, then test only runs once. If probe test interval is set then test run continuously from start point and at each interval time. Test stops when changed back to NO. Probe temp must be >= the minimum probe temperature setting.

Sets time interval between automatic probe tests, 0 disables automatic testing.

Sets maximum impedance for

Probe alarm

Sets maximum Probe recovery time, timer cut short if probe recovers faster. The

Probe alarm is set if the probe signal does not recover while this timer is active.

The period of time when air is allowed to flow to the tip of

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Parameter Name Units or Options Range

Dew Point

BURNOFF

RECOVERY

MIN PROBE TEMP

SECONDS

F OR C

0 – 999

1100° – 2000° F

590° – 1090° C

Description the sensor.

Recovery time for probe following the burnoff test.

The PROBE alarm is set if the probe signal does not recover before this timer expires.

Minimum temperature for probe impedance and verification tests.

Table 8 Analog Output Menu ( AOUt)

Parameter Name

ANALOG 1 UNIT

Units or Options Range

DEWPT, LInA,

TENP, POUT,

PO1, PO2,

PROG, LInB

Description

4 to 20mA output. DEWPT – retransmits

DEWPT if DEWPT is selected as process source.

LInA – scaled millivolt value of input A depends on which input selected as process source.

TENP – probe temperature when DEWPT is selected as process source and a thermocouple type is selected.

POUT – Power output is available for the controller, allows for –100% to 100% for split actuators. PO1 or

PO2 allow for just 0 – 100% output for either control contact.

PROG - allows the output to be controlled from the

DACV1 memory location.

LInB – scaled millivolt value of input A depends on which input selected as process source.

ANALOG 1 OFFSET Offset for selected process value or percent output.

-30.0 to 300.0 for

DEWPT, LInA or

LInB

-300 to 3000 for temperature

LOPO for POUT

This is the minimum value of the process associated with the 4mA output. The magnitude of this number is based on the display resolution.

In POUT mode the offset is fixed to the LOPO value.

When PROG is selected the

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Parameter Name Units or Options Range

ANALOG 1 RANGE Span scaling for selected process value or percent output.

0 or

DAC_OFFSET for PROG

0 to 9999 for

DEWPT, LInA,

LInB, and Temp

HIPO for POUT

4096 or

DAC_SPAN for

PROG

ANALOG 2 UNIT CARB, LInA,

TENP, POUT,

PO1, PO2, PROG,

LInB

ANALOG 2 OFFSET Offset for selected process value or percent output.

ANALOG 2 RANGE Span scaling for selected process value or percent output.

Table 9 Alarm Menu (

ALr)

Parameter Name

ALARM 1 TYPE

Units or Options

OFF

FSHI,

FSLO dUbd dbHI dbLO

HIPO

LOPO

FALt

PROB tinE

Strt

SOAk

Range

Dew Point

Description offset is fixed at 0

This is the maximum value of the process associated with the 20mA output. The magnitude of this number is based on the display resolution.When POUT is selected this value is fixed to the HIPO value.

When PROG is selected the range is fixed at 4096

Same as Analog 1

Same as Analog 1

Same as Analog 1

Description

OFF disables alarm contact.

FSHI - Full Scale HI, active when process is above

ALARM 1 VALUE.

FSLO - Full Scale LO, active when process is below

ALARM 1 VALUE.

dUbd – Deviation Band available for the controller only, active when process is outside of symmetrical band around setpoint.

dbHI – Deviation High, defines a process band above the process setpoint. The alarm is active if the process moves outside this band.

dbLO – Deviation Low, defines a process band below the process setpoint. The alarm is active if the process

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Parameter Name Units or Options Range

ALARM 1 VALUE

ALARM 1 ACTION REV, LREV, DIR,

LDIR

ALRM 1 TM ON DLY 0 – 250 SECONDS

ALRM 1 TMOFF DLY 0 – 250 SECONDS

ALARM 2 TYPE Same as ALARM 1

TYPE

ALARM 2 VALUE

ALARM 2 ACTION

ALRM 2 TM ON DLY 0 – 250 SECONDS

OFF

ALRM 2 TMOFF DLY 0 – 250 SECONDS

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Dew Point

Description moves outside this band.

HIPO – Output High, this alarm sets the threshold for the maximum control output allowed which is set by

ALARM 1 VALUE.

LOPO – Output Low, this alarm sets the threshold for the minimum control output allowed which is set by

ALARM 1 VALUE.

FALt – Fault, open inputs for mV, thermocouple or hardware fault.

Prob – Probe, fault active if impedance or verification are out of range.

tinE – Time, establishes alarm contact as the contact used for the End alarm.

Strt – Start, same as Time.

SOAk – Soak, same as Time.

Trigger set point value

REV = Reverse (N.C.) can be acknowledged even if the condition still exists.

LREV = Latched Reverse

(N.C.) can not be acknowledged if the condition still exists.

DIR = Direct (N.O.) can be acknowledged even if the condition still exists.

LDIR = Latched Direct

(N.C.) can not be acknowledged if the condition still exists.

Delay ON time for ALARM1

Delay OFF time for

ALARM1

Same as ALARM 1 TYPE

Trigger set point value

Same as ALARM 1 ACTION

Delay ON time for ALARM2

Delay OFF time for

ALARM2

Marathon Monitors Inc.

Table 10 Communication Menu (

HOST)

Parameter Name

PROTOCOL

ADDRESS

BAUD RATE

PARITY

Units or Options Range

PROP OR BUSS

1 TO 15 (MMI)

NA,600,1200,

2400,4800,9600,

19.2K,38.4K

None/Even/Odd

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Description

PROP is Marathon Monitors ,

Inc. slave protocol, BUSS is

RTU Modbus protocol.

DELAY NONE, 10, 20, 30

Modbus uses None parity only.

NONE = 0 Delay, other selections are millisecond delay in response.

Table 11 Info Menu (

InFO)

Parameter Name

MILLIVOLT TEMP

IN

Units or Options Range

MILLIVOLTS

MILLIVOLT PROB IN MILLIVOLTS

-10-100

0-2000

COLD JUNCTION

BURNOFF MV

BURNOFF TEMP

DEG (F OR C)

PERCENT OUTPUT % Output

PROB IMPEDANCE Kohms

IMP RECVRY TIME SECONDS

MILLVOLTS

°F OR °C

0 – 60°C

LOPO to HIPO

0 – 100

0 – 250

0 – 2000

0 – 2000

Description

Displays direct mV of

Temperature input

Displays direct mV reading of probe input

Displays actual cold junction temperature

Displays actual % output

Displays last probe impedance value.

Displays last impedance recovery time.

Millivolts read at the end of the probe burnoff cycle

Displays probe temperature read at the end of the probe burnoff cycle

BURNOFF RECVRY

TIME

NEXT TEST

FIRMWARE REV

SECONDS

Hours.tenths

Version number

0 – 250 Time taken for probe to return to 98% of pre-test millivolt reading.

Time to next probe test, shows 00.0 if test automatic test is disabled.

Parameter Name

CAL INPUT

Table 12 Calibration Menu

Units or Options Range

NO / YES

Description

Default to NO, must be

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Marathon Monitors Inc. Dew Point

changed to YES to enter input calibration routine.

TC mV ZERO

(CAL IN)

TC mV SPAN

(CAL IN)

PROBE mV ZERO

(CAL IN)

PROBE mV SPAN

(CAL IN)

CJ OFFSET

(CAL IN) thermocouple zero thermocouple span millivolt zero

CAL OUTPUT

OUTPUT 1 MIN

(CAL OUTPUT)

OUTPUT 1 SPAN

(CAL OUTPUT)

NO / YES

0 – 60° C

0 – 140° F millivolt span

Sets the cold junction offset depending on the temperature range selected

Default to NO, must be changed to YES to enter output calibration routine.

Sets signal level for the minimum mA output.

Sets signal level for the maximum mA output.

OUTPUT 2 MIN

(CAL OUTPUT)

OUTPUT 2 SPAN

(CAL OUTPUT

Sets signal level for the minimum mA output.

Sets signal level for the maximum mA output.

Pressing the Setup key once at any point in the Setup menu will return the instrument to the normal process display.

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Dual Key Functions

The VersaPro was four dual key functions as defined below:

RIGHT arrow / Enter

LEFT arrow / Enter

DOWN arrow / Enter

Rem / Enter

Start probe test sequence

Start Timer

Edit Remaining Timer

Monitor Mode

Starting Probe Tests

Pressing the RIGHT arrow / Enter keys simultaneously will start the probe tests if a probe test function has been selected in the Probe Setup Menu, parameter Probe Test, and the probe temperature is above the minimum probe temperature parameter in the same menu.

If there is a value other than 0 entered in the Probe Test Interval parameter the probe test will be preformed after the selected interval time has elapsed from the time the test was manually started. If the interval time is set to 0 then no additional tests will be preformed until the next manual start. Starting the test through this dual key function is the same as if the Start

Test parameter in the Probe menu had been changed from NO to YES.

Start Timer

Pressing the LEFT arrow / Enter keys simultaneously will start the timer if the timer has been enabled in the Control Setup menu, the timer set point is greater then zero, and an alarm contact has been assigned a timer function. Press both keys while the timer is running will stop the timer.

Edit Timer

Pressing the DOWN arrow / Enter keys simultaneously while the timer is running will allow the remaining time to be changed. The remaining time can be increased or decreased. The change in time takes effect when the Enter key is pressed and the display returns to the normal remaining time display.

Monitor Mode

Monitor Mode is used by factory personnel only. Return to operate mode by cycling power or sending the appropriate command word to the instrument.

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Digital Input Event

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The VersaPro has a single digital input. This input is activated by making an isolated contact closure between terminals TB-B 11 and 12. This input is debounced for a momentary closure of at least 0.6 seconds.

NOTE

Do not connect either terminals TB-B 11 or 12 to any AC or DC potentials. These terminals are internally connected to an isolated 5VDC source. Use only an isolated contact closure across these terminals.

The input event can be set to any one of the following functions: OFF, PrOb (start probe test), AUTO (set to auto), rEn (set to remote), ACK (alarm acknowledge), PrOC (process hold), Strt (timer start), HOLd (timer hold), End (timer end acknowledge). These settings can be selected in the Input Setup menu at the DIG EVENT parameter. The selections can be made by pressing the up or down arrow keys and then pressing the Enter key.

OFF

This selection disables the input event function. This is the default condition of this feature unless another function is selected.

PROB

This selection will start the impedance (10Kohm) test and/or probe burnoff. The various probe tests will run only if they are selected in the Probe Menu. The PrOB input event will have no effect if no probe tests are selected.

If a probe test interval time is set to any value other than zero, activating this function will reset the interval count down timer. If the probe test interval time is set to zero this function will operate only when the contact closure is made across the event input terminals. The contact closure must open and close each time to initiate another probe test.

AUTO (controller only)

This selection will force the instrument from manual mode or remote mode into local automatic mode. No change will occur if the instrument is already in automatic mode.

rEn (controller only)

This selection will force the instrument from local setpoint mode or manual mode into remote setpoint mode. No change will occur if the instrument is already in remote setpoint mode.

ACK

This selection will acknowledge any latched active alarm except the timer end alarm.

This function will have no effect if the alarm condition persists when the acknowledge signal is issued. This function resets a latched alarm similar to pressing the Enter key.

PrOC

(controller only)

This selection will place the process calculation in hold. The control output is also held at the output level when the process hold event was set. This includes

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all analog output signals as well as control contacts. This is similar to the state the instrument is set to when the probe tests are running.

Strt

(controller only)

This selection will start the timer function if the timer is enabled, the set point is greater than 0, and one alarm contact is assigned to a timer function.

HOLd

(controller only)

This selection will place the timer in a hold state for as long as the event input is active.

End

(controller only)

This selection will acknowledge the end condition of the timer, clear the end state, and reset the timer for another start.

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Timer Function

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The Versapro timer function is available on all process controller options. The timer can operate independently or it can be dependent on the process based on how either alarm contact is configured. The instrument has three possible functions; timer, guaranteed start timer, and guaranteed soak timer. These functions are set through the mode selection of alarm 1 or alarm 2 in the Setup menu. Only one alarm should be set to a timer function at any time.

The timer will only work if three conditions are met; the timer function must be enabled in the

Setup Control Menu, an alarm contact must be configured for a timer function, and the timer set point must be greater then zero.

The timer set point is set in the Setpt Key menu. The remaining time is displayed in the display cycle list and can be edited when the timer is running. The timer set point is entered in whole minutes. The remaining time will show the tenths of a minute if the timer is less than 1000 and shown as whole minutes. The timer start setting follows the remaining time display in the Setpt

Menu.

Setting the Timer

The first step for using the timer is to enable the timer function in Setup Control Menu. This allows the timer to be started in various ways and also allocates a serial port channel for the timer.

The next step is to move to the Alarm menu and select a timer function for one of the alarms.

The alarm that is selected will close its alarm contact with the timer counts to zero. Only one alarm should be selected for a timer function and any time.

NOTE

Do not set both alarms to timer functions at the same time.

The final step is to press the Setpt key and the Enter key until the TIMER SETPT parameter appears. Enter the desired value of the timer. This value is the only set point for the timer.

This value will be used as the timer set point if the instrument is in the local automatic or remote control mode. There is no separate remote timer set point value. The local timer set point value will be over written by the value received from a remote device like a computer or master instrument.

The final step is to start the timer. This can be done in the Setpt menu by pressing the Enter key until the TIMER START parameter appears and selecting ‘YES’. The timer can also be started by pressing a dual key sequence LEFT arrow and Enter, through the serial interface, or through the digital event input.

Timer Dual Key Functions

⇐ + Enter

In Auto or Remote mode this two key combination will activate or deactivate the timer function.

 + Enter

This two key combination allows the timer function remaining time to be edited.

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The behavior of the timer is controlled through the selection of the alarm modes. If no timer alarm is selected for either alarm 1 or alarm 2 then the timer will not start. The Time, Start, or Soak alarm modes must be selected for one alarm contact before the timer will start.

The Rem LED on the front panel will flash while the timer is active in the RUN, HOLD, or

END modes. The timer will go inactive when END is acknowledged or if the timer is disabled.

The timer can be stopped by pressing the Enter and Right arrow keys during an active RUN state, sending a remote timer set point of 0 when the instrument is in remote mode, or by changing the remaining time to zero.

The Event Input can be configured to start the timer, hold the timer, or acknowledge the End state.

Time

The Time alarm mode it will run continuously once it has started and the alarm contract will close when the remaining time reaches zero. The alarm value has no effect in the simple timer mode and the timer will not stop or hold if the process value changes. The alarm message is ‘End’ will display on the LCD screen and the appropriate alarm contact will activate.

Guaranteed Start Timer

The guaranteed start timer function works in conjunction with the alarm value. The timer will hold until the process value is greater then the lower band value of the process. The alarm value is the band value. In the figure below the alarm value is 10, which represents a band around set point of

∀10°. The timer will not HOLD once it has met the initial starting conditions. The process can fluctuate outside of the alarm band after the timer has started without placing the timer in a HOLD state. The following figure shows the behavior of the guaranteed start timer.

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Marathon Monitors Inc. Dew Point

Figure 5 Guaranteed Start

Guaranteed Soak Timer

The guaranteed soak timer works in conjunction with the alarm process value. The alarm value is the valid band around the process set point. The process must be within the band around the process set point to start the timer once it has been activated. If the process passes above or below the alarm band setting, the timer will go to a HOLD state. The timer will be allowed to continue only when the process is within the band setting. In the following figure the alarm value is set to 10 degrees for a temperature process.

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Marathon Monitors Inc. Dew Point

Figure 6 Guaranteed Soak

Timer Alarm Behavior

The alarm contacts do not work like normal process alarms when the timer, soak, or start timer functions are selected. If the alarm is configured for the timer, the contact will only activate when the remaining time counts down to zero and the timer reaches the END state.

Once this occurs the END Alarm message will appear on the LCD display. The alarm will stay latched until it is acknowledged by pressing the Enter key or closing a contact across the

Digital Event terminals if the End setting is selected as the Digital Event function. The Rem light flashes during the END state and stops flashing when the timer is acknowledged and returns to the IDLE state.

Timer State Diagram

The following diagram shows the conditions that control the state of the timer function.

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Marathon Monitors Inc.

Timer Enable = NO OR

Timer Start = NO OR

Enter key OR

Remote Time Setpt = -1 OR

Event(END) = ON

IDLE

Timer Enable = YES

Timer Start = NO

Remaining Time = 0

END

Time Enable = YES

Timer Start = YES

Display = END Alarm

End Alarm = ON

Alarm contact = ON

Rem Light = Flash

Timer Enable = NO OR

Timer Start = NO OR

Remote Time Setpt = -1 OR

Enter/Left arrow

Remain Time counts to 0

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Event(STRT) = ON OR

Remote Timer SP = -2 OR

Enter / Left arrow OR

Timer Start = YES AND

Timer SP > 0

RUN

Timer Start = YES

Remain Timer = countdown

Time Alarm = OFF

Alarm Contact = OFF

Rem Light = Flash

Event(HOLD) = OFF OR

Time Alarm = OFF

Event(HOLD) = ON OR

Time Alarm = ON

Timer Enable = NO OR

Timer Start = NO OR

Remote Time Setpt = -1 OR

Enter / Left arrow

HOLD

Timer Start = YES

Remain Time = hold

Time Alarm = ON

LCD Display = Hi/Lo Alarm

Alarm Contact = OFF

Rem Light = Flash

Figure 7 Versapro Timer State Diagram

The timer has four states. The IDLE state is the inactive condition. The RUN state is the active state when the timer is counting down. The HOLD state is when counting is paused due to either Digital Event = HOLD or a configured alarm is active. The END state is when the timer has timed-out but has not been acknowledged. The configured alarm contact will activate when the END state is entered.

The following is a summary of ways to change the state of the Timer. These assume the standard setups are in effect. It is assumed that the Timer is enabled for it to start or run.

Timer will start if:

1.

Timer Enable = YES and

2.

3.

4.

5.

6.

7.

Alarm is set to timer function and

Timer Setpoint > 0 and

Digital STRT event = ON or

Enter/Left keys = CLOSE or

Timer Start = YES or

Remote Setpoint = -002

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Marathon Monitors Inc.

Timer will hold if:

1.

2.

Digital HOLD event = ON or

Alarm Soak or Run deviation is active

Timer will run if:

1. Timer Enable = YES and

2. Timer Start = YES and

3. Timer Setpoint > 0 and

4. Digital HOLD event = OFF and

5. Remaining Time > 0

Timer will reset to IDLE without activating END if:

1.

Enable = NO or

2.

3.

Timer Start = NO or

Remote Timer setpoint = -001 or

4.

Enter/Left keys pressed

Dew Point

Timer goes to END state if:

1.

Timer count down reaches 0

Timer returns to IDLE state from END when:

1.

Enable = NO or

2.

3.

Timer Start = NO or

Operator presses Enter key or

4.

Remote Timer setpoint = -001 or

Digital END input = ON

5.

Timer SIO Operations

The Versapro allocates a second host address if the timer function is enabled and the host port protocol is set to PRoP (Marathon) using the Marathon slave protocol. If the host port protocol is set to buss (Modbus) or the Marathon block protocol is used, then the timer information is accessed directly. For the Marathon slave protocol, the first address is the primary address set by the Address parameter setting in the Setup HOST menu. The second address is assigned as Address +1 and will respond to 10Pro type commands. The setpoint commands affect the timer set point. The initial state conditions must be met for the timer to run.

The remaining timer value will be transmitted as the process value when responding in

10Pro slave mode. The timer values and process values are available at the host address if the instrument is responding to the Marathon block command or Modbus. The Address + 1 address is always active while the timer is enabled and the serial port protocol selection is

MMI and inactive when Modbus is selected. It is important to consider this extra address allocation if multiple slaves with timers are going to be connected to a master. Only eight addresses are possible when the 10Pro command mode is used. See the section on serial communication for details on these differences. If only the Marathon block command is going to be used then the instrument will not respond on the second address.

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In the MMI 10Pro protocol, the value returned for the percent output command is the timer control byte. The bits in the control byte are defined in the following table.

Timer Control Byte

0

1

2

Bit Description

Timer Enabled

Timer Running

End

Purpose

Indicates that the timer is enabled in the setup menu.

Indicates that the timer has started.

Indicates that the timer has timed out and not acknowledged.

3 Hold

4 & 6 N/A

Indicates that the timer is in hold mode.

Not used.

7 Control Set when the timer is started. Reset when timer has stopped. Is toggled by the Enter + Left Arrow or set by the SIO sending a time setpoint.

Controlling the Timer Remotely

All timer setpoint values must be written to the host address + 1 and the timer function must be enabled in the instrument control menu for the instrument to recognize any host address +

1 command.

Control of the timer via the serial port using the 10Pro commands has limited capabilities since the only value that can be written is the time set point. There are special cases if the

Versapro is connected to Dualpro/Multipro as a slave. The master instrument must first send a valid setpoint value from 1 to 9999. The master can then send a setpoint of –002 to start the timer assuming all other configuration requirements are met. If the master sends a setpoint of –001 the timer is reset and stopped with no End alarm.

The master can set the timer functions, alarm values, and delay times using the Marathon

Block or Modbus protocols. The sequence of events is similar for either Marathon Block or

Modbus protocol.

The timer control word is located at parameter 70, Timer Control and Event (TCE). The timer control byte is the upper byte of this word. The input event configuration is in the lower byte of this word. Any configuration of the input event must be added to the timer function values when this word is written to the Versapro. In this example the event configuration is set to none (0). It is suggested that this word be read by masking the upper byte of the word to record the input event configuration. This value can then be added to the following timer control values to retain the input event configuration.

The timer will only work when it is enabled, the timer setpoint is greater then 0, and at least one alarm mode is set to a timer function. The alarm mode has to be manually configured.

Programming the timer involves the following sequence:

Enable the timer by writing a value 32768 (0x8000) to TCE.

Set the timer setpoint by writing setpoint value to parameter 3 (TSETPT)

Start the timer by writing a value 33024 (0x8100) to TCE.

The timer will indicate that it has timed out when TCE changes to value 34560

(0x8300).

Acknowledge the end alarm by writing a value 0 (0x0000) to TCE.

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A description the TCE word and the timer flags in the TCE word can be found in the

Versapro Memory Map table.

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Probe Impedance Test

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The probe impedance test is performed by measuring the open circuit voltage of the probe, applying a known shunt resistor across it and measuring the shunted voltage output. The value of the shunt resistor is 10kohm for DEWPT sensors.

To run a probe impedance test it is necessary setup the probe testing parameter in the

SETUP Probe Menu. Please refer to Probe parameters table for an explanation of these setup parameters. It is necessary to have the impedance (RES) test or both (BOTH) selected at the PROBE TEST parameter in order to run the impedance test. You may choose to accept the defaults for the other parameters in this menu or change them to suit your applications.

NOTE

It is necessary that the sensor be above the MIN PROBE TEMP parameter setting for this test to run. It is also necessary that the probe is measuring a stable process gas during this test.

There are two ways to start this test. From the Probe Setup menu at the START TEST parameter, you can change this parameter from NO to YES and then press the ENTER key.

The instrument will exit the Setup mode and display the test name and sequence number on the front display. The LCD display will indicate “IMPEDANCE TEST” while the lower

LED display will show the test sequence number as listed in the following table.

It is also possible to start the test in the process display mode by pressing the ENTER and

RIGHT ARROW keys at the same time. The test can be stopped by returning to the START

TEST parameter and changing YES to NO and then pressing ENTER or by pressing the

ENTER and RIGHT ARROW keys again.

If the TEST INTEVAL parameter has a number other than 00.0 then the test will continue to run each time the test interval timer counts down to 0. This test interval can be stopped by setting the interval timer to 00.0.

The following table explains the various operations of the impedance test.

Sequence #

1

2

Table 13 Probe Impedance Sequence

Description

Inhibit process variable calculations. Freeze all process controls and outputs.

Freeze alarms at last state except clear any previous probe test failure alarm.

Store present probe millivolt reading

Apply shunt resistor across probe

Wait for impedance test timer, fixed time of 30 seconds

Compute impedance of probe and remove shunt resistor. Save measured impedance as

PROBE IMPEDANCE in INFO menu.

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Sequence # Description

If impedance is greater than PROBE IMP

LIMIT then set probe test failure alarm.

Dew Point

3 Wait for probe to recover to >=99% of original millivolts.

Evaluate actual recovery time to IMP

RECVRY TIME

If recovery time is greater than IMP RECVRY

TIME then set probe test failure alarm.

Store recovery time (or max value ) as IMP

RECVRY TIME in INFO menu

4 If verification is to be performed then go to step 1 of verification sequence

Otherwise wait 30 seconds and resume normal operation of all instrument functions.

Why Measure Sensor Impedance?

It is important to track sensor impedance over a period of time to help determine the replacement schedule for the sensor. A high impedance (>50 K

Ω) indicates that the electrode contact on the probe zirconia has deteriorate to a level that probably warrants replacement. High sensor impedance results in a lower signal output from the sensor and an eventual failure of the electrode connection on the process side of the zirconia ceramic. This deterioration is more of a factor in highly reducing atmospheres. In such applications, it may be necessary to check the impedance at least once a month. Under light reducing, annealing, or brazing operations, the impedance may not have to be check unless there is a question about the probe’s performance.

A typical impedance for a new probe is less than 1 K

Ω. As the probe starts to age the impedance will increase. Past 20 KOHM the sensor should be monitored more closely.

Above 50 K

Ω, the sensor should be replaced. If it is necessary to replace the sensor, remove it carefully, following the instructions supplied with the sensor. Do not discard a sensor with a high impedance. It may be possible to rebuild the sensor if the ceramic parts are intact.

Contact Marathon Monitors , Inc. for information on rebuilding your sensor.

An impedance test can only be performed if the probe temperature is at or above 1300°F with stable atmosphere present. The instrument freezes all control functions and process signals during the test.

A 10

Ω resistor is shunted across the sensor output. The sensor impedance is calculated as:

Rx = [(Eo/Es)-1]*Rs

Where Rx = sensor impedance, Eo = sensor’s open circuit voltage, Es = shunted sensor’s voltage, and Rs = shunt resistor. The units of Rx are the same as Rs.

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Marathon Monitors Inc.

Probe Burnoff

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Probe burnoff is performed by flowing air into and around the oxygen sensor internal ceramic substrate. This air creates a flame at the tip of the sensor that burns off any accumulated DEWPT or soot. A ¼” CPI compression fitting at the mounting hub of

Marathon Monitors sensor is provided for the air connection. This air floods the probe sheath and flows out and around the sensor. The sensor does have to be above the MIN

PROBE TEMP parameter found in the PROBE setup menu. This value is typically 1300°F or higher.

To run a probe burnoff it is necessary setup the probe test parameters in the SETUP Probe

Menu. Please refer to Probe parameters table for an explanation of these setup parameters.

It is necessary to have the burnoff (BOFF) test or both (BOTH) selected at the PROBE

TEST parameter in order to run the burnoff. You may choose to accept the defaults for the other parameters in this menu or change them to suit your application. It is necessary that the sensor be above the MIN PROBE TEMP parameter setting for this test to run. It is not necessary for the probe to be measuring a stable process gas during this test.

There are two ways to start this test. From the Probe Setup menu at the START TEST parameter, you can change this parameter from NO to YES and then press the ENTER key.

The instrument will exit the Setup mode and display the test name and sequence number on the front display. The LCD display will indicate “BURNOFF TEST” while the lower LED display will show the test sequence number as listed in the following Table.

It is also possible to start the test in the process display mode by pressing the ENTER and

RIGHT ARROW keys at the same time. The test can be stopped by returning to the START

TEST parameter and changing YES to NO and then pressing ENTER.

If the TEST INTEVAL parameter has a number other than 00.0 then the test will continue to run each time the test interval timer counts down to 0. This test interval can be stopped by setting the interval timer to 00.0.

Readings are averaged to eliminate variations in measurement due to initial flow conditions.

There are three operator inputs for verification time periods;

• TEST INTERVAL is an interval timer that sets the time between automatic verifications in hours and tenths. The verification can be manually initiating by pressing and holding the Enter key and then the Right Arrow key. Setting the test interval time to zero disables automatic testing.

• BURNOFF TIME is the period in seconds burnoff air is flowing to the sensor.

• BURNOFF RECOVERY is the time period in seconds that allows the probe to recover and return to the process level.

The following table outlines the actions the instrument takes at each sequence step.

Table 14 Probe Burnoff Sequence

Sequence #

1

Description

Inhibit process variable calculations. Freeze all process controls and outputs.

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Marathon Monitors Inc.

Freeze alarms at last state except clear any previous probe test failure alarm.

2

3

Close burnoff contact and wait the BURNOFF time period.

Release the burnoff contact and wait the

BURNOFF RECOVERY time period.

Save the mV reading as in INFO menu.

Resume normal operation of all instrument functions.

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Marathon Monitors Inc.

Procedure to Test the Sensor

Dew Point

The following section describes the steps required to do an automatic or manual test of an oxygen sensor using the Versapro controller or monitor.

Correctly set up the parameters in the VersaPro for the Probe Testing.

1. Press the SETUP key for five seconds to activate the setup mode

2. Page to the Prob Menu heading by pressing the RIGHT or LEFT arrow keys. When

Prob appears in the LCD display, press the Enter key.

3. The first parameter is probe test. Press the UP or Down Arrow keys until the lower display reads Both. Press the Enter key to advance to the next parameter.

4. The next parameter is the Start Test. The default setting is NO. This parameter will change to YES if the probe test is running or if the interval timer is running.

5. The next parameter is the Test Interval (hours). This should be set to 0 for a manual start test. A flashing cursor in the lower LED display indicates which digit can change if the parameter value is numeric. The UP or DOWN arrows increase or decrease the digit value. The RIGHT or LEFT arrow keys move the cursor to the right or left digit. If a number is entered here it is the interval in hours between automatic repeats of the probe test. The probe test must be started manually the first time to initiate the repeat function.

6. The next parameter is the Probe Impedance Limit. This should be set to 20 (Kohms).

This setting is where the sensor electrodes are starting to wear and should be watched. If the impedance reaches 50 Kohms, the sensor should be replaced.

7. The next parameter is the Impedance Recovery Time (seconds). The default value is 30.

This value should always be greater than the millivolts filter value in the Input menu.

8. The next parameter is the Burnoff Time (seconds). The default value is 30. This value typically should not exceed 60 seconds if burnoff is being done at regular intervals.

9. The next parameter is the Burnoff Recovery (seconds). The default value is 30. This value may have to be increased if there is low re-circulation in the furnace.

10. The next parameter is the Minimum Probe Temperature. This should be set to 590 if C is used or 1100 if F is used.

11. After pressing the ENTER key for the last parameter, press the SETUP key to exit the

Menu and return to regular process operation.

To manually start a probe test procedure

1. Simultaneously press the RIGHT arrow/Enter keys with the display in normal process mode.

2. The instrument will cycle through the test steps and return to normal operation after completing the test if results are satisfactory.

3. You may access the results by cycling the display with presses of the Enter key. If a probe fault alarm is displayed it will be necessary to go to the Info section of the

SETUP Menu. The measured probe impedance, probe impedance test recovery time, probe millivolts and probe temperature during burnoff, and burnoff recovery time are listed.

If a Probe Fault occurs

To clear a Probe Fault alarm, you must run a successful probe test procedure, also see the

Troubleshooting section of this document.

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Marathon Monitors Inc. Dew Point

Access the Probe Test Results data from the Info section of the SETUP Menu. Check the probe impedance and recovery times against the parameter settings in the Probe setup section. If necessary, adjust the test parameters to allow a successful test. Take the necessary actions to correct the problem.

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Tuning

Dew Point

Before attempting to tune the instrument make sure you understand the Operation and Setup part of the instrument.

What is tuning?

Tuning the controller means that the control characteristics of the controller are matched to those of the process in order to obtain hold the process to setpoint. Good control means:

• Stable, ‘straight-line’ control of the process variable at setpoint without fluctuation

• No (minimum) overshoot, or undershoot, of the process variable relative to setpoint

• Quick response to deviations from the setpoint caused by external disturbances, thereby rapidly restoring the process variable to the setpoint value.

Tuning involves calculating and setting the value of the parameters listed the following table. These parameters appear in the Control Setup menu.

Table 15

Parameter

Proportional band

Meaning or Function

The bandwidth, in display units, over which the output power is proportioned between minimum and maximum.

Integral time

(Reset)

Determines the time taken by the controller to remove steady-state error signals.

Derivative time

(Rate)

Determines how strongly the controller will react to the rate-of-change of the measured value.

Cycle Time The total amount of time used to calculate the combination of percent on and percent off periods of the control function.

The Versapro uses the Proportional Band as a representation of the Proportion section of

PID, the Reset as a representation of the Integral section of PID, and the Rate as a representation of the Derivative section of PID. Thus by following a simple procedure, PID tuning can easily be implemented in any control situation. A suggested procedure is diagramed in the next figure.

All of the PID parameters may be altered by changing these parameters in the Setup / Ctrl menu. The following procedure assumes the initial PID values for a typical batch furnace.

You may be able to start with a proportional band setting of 10 or less for a smaller box or temper furnace.

You must determine want the initial cycle time should be. If you are using control motors or continuous motors, set the cycle time to the time it takes the control motor or actuator to

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fully open and fully close. If you are using quick acting solenoids to control the process the cycle time setting is a compromise between longer times to limiting contact cycles and extend the life of the actuator or shorter times to maintain good control. A good rule is to watch to process value and turn on the solenoid. Measure the time it takes for the process to react with a 5% change. Double this time and enter it as the cycle time. Decrease the cycle time to get a smoother control.

If, after following the procedure, the process continues to oscillate, it may be necessary to change the HIPO or LOPO parameters. Make sure that the control output is linear through the full range from LOPO to HIPO. In situations where the system is difficult to tune, it is most likely the output is not linear or there is too much lag time between the control command and measurable changes in the process. Test the system in manual mode to verify the output is linear.

A much higher proportional band may be necessary for extreme lag in the process response.

In most cases, the derivative part of the control equation is not necessary. Generally, furnace control can be maintained using only the proportional band and the reset parameters.

Make sure you record all operating parameters and keep them in a secure place for later reference.

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Figure 8 PID Manual Tuning Procedure

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Scaling Analog Inputs

Dew Point

If either input is set to Linear mode the displayed value for that input can be scaled to desired engineering units. This is helpful if the measured linear value has to be scaled and re-transmitted on one of two analog output channels.

Using the equation y = mx + b, where

Y is the desired engineering unit to be displayed

X is the linear millivolt value

M is the Slope of the y/x relationship

B is the y intercept

Linear A Example

Let us use Input A input for a linear oxygen transducer that outputs a 0mV to 53.2mV signal for a 0% to 100% oxygen range. Since both the signal output and the process minimum are both 0, the Input A offset will be 0.

The slope can be calculated by dividing the maximum process value (100) by the maximum input level (53.2mV). This gives a slope value of 1.879. This number can be entered as the

Input A slope. The decimal point can be shifted by placing the flashing cursor on the most significant digit and pressing the Left arrow key until decimal point shifts to the required position.

These scaling values will produce a process value of 100.0160% DEWPT for a maximum sensor input of 53.2mV. The process display can be configured to display either 100 or

100.0. This process value can then be retransmitted to other control devices are a recorder.

The control model of the Versapro will be able to control to a set point for the new process value.

Keyboard Function during Input Slope

The four digits in the slope display can be change from 0 to 9 or the left digit and change to the negative sign. This most significant digit position also allows you to shift the decimal point by pressing the LEFT arrow key. The decimal point will shift from first digit to the third digit as the LEFT arrow key is pressed. Pressing the RIGHT arrow key when the cursor is on the least significant digit will shift the decimal point to the right.

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Scaling Analog Outputs

Dew Point

The analog outputs are scaled as simple offset and span values. For example if analog output 1 is to be scaled for a 0 to 46.0° dew point value, the offset value would be 0 and the span value would be 46.0.

It is possible to narrow the range of the output even if the instrument can measure a larger process range. If a smaller range of dew point were to be retransmitted it would be necessary to change the offset value to the lowest value to be retransmitted. The span would be set to the highest value. For example if a dew point span of 20° to 50° was to be retransmitted then the offset would be 20.0, the span would be 50.0. The full 4mA to 20mA output range would respond to this narrower range of dew point.

The same rules apply to analog output 2. The range of the offset and span numbers depends on the range of the process value that has been selected for either analog output.

Additional selections for Power Output and Program mode have fixed offset and span values. The power output offset and span values are fixed to the LOPO and HIPO values selected for the control outputs under the Setup Control menu.

The Program mode selection has a fixed offset of 0 and a fixed span of 4096. When this output mode is selected the analog output can only be changed by writing a value to either the DACV1 or DACV2 registers.

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Calibration

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There are two analog inputs, a cold junction compensation sensor, and two analog outputs on the VersaPro. The input level is determined by which terminals are used for the input signal.

There are two pairs of input terminals: TB-B 1, 2 for the thermocouple (T/C) input and TB-B

3, 4 for the probe millivolt input.

The 4 – 20mA analog outputs are at TB-B 5, 6 and TB-B 7, 8.

The following is a brief description of input/output and its specifications.

Input

-10

± 2 μV b) Probe mV Input to

± .1 mV, linear

Calibration Displays and Keyboard Operation

When entering the Calibration Menu, the operator has to answer one of two questions depending on which I/O functions have to be calibrated. If the CALIBRATION IN prompt is answered with a YES, then the parameters related to the thermocouple input, millivolt input, and cold junction can be changed. If this prompt is skipped by pressing the Enter key, then a second prompt, CALIBRATION OUT is displayed. If this prompt is answered with a

YES, then the zero and span values for both analog outputs can be changed.

In the Calibration Menu the displays and front panel keys take on special assignments. The

LCD display shows the input and calibration point being calibrated. The upper LED display indicates that the instrument is in CAL mode. The lower LED display indicates the actual input level for the input channels or the calibration factor for the output channels.

It is very important that the display is indicating the proper I/O parameter before making an adjustment or the wrong value will be changed.

For the CAL INPUT calibration mode, the following keys perform the described functions:

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UP ARROW

DOWN ARROW

RIGHT ARROW

Increases the displayed value.

Decreases the displayed value.

Shifts the flashing digit to the right and decreases the amount of adjustment or sensitivity of the adjustment.

LEFT ARROW Shifts the flashing digit to the left and increases the amount of adjustment or sensitivity of the adjustment.

ENTER

SETUP

Advances to next input value and saves the calibration changes.

Exits the calibration mode.

Preparing for Input Calibration

The following is required to calibrate thermocouple and millivolt inputs:

Calibrated millivolt source, 0 – 2000mV with a 0.1 mV resolution

Calibrated microvolt source, -10mV to 50mV with a 0.1 uV resolution.

Copper wire to connect the millivolt source to the instrument.

Calibrated thermocouple simulator with internal cold junction compensation

Thermocouple extension wire for the type of thermocouple to be used.

In the Input Setup menu, select the thermocouple type to be used in the process. Enable

Cold Junction Compensation.

The first part of the calibration is in linear mode first. The thermocouple setting has no effect on the millivolt readings in the first part of the input calibration but will effect the reading during the cold junction adjustment.

Calibration of the Thermocouple Input

Calibration procedure:

1. Connect terminals TB-B 1, 2 to an isolated, stable millivolt source calibrator using standard copper wire, 20 AWG is sufficient.

2. Set the calibrator output to 0.00 mV.

3. Activate the calibration mode by entering the SETUP menus, selecting the Calibration menu and changing Calibration IN - NO to YES.

4. Use the Enter key to select the TC ZERO mode.

5. Using the arrow keys, adjust the displayed value to equal the calibrator input.

6. Press the Enter key to select the TC SPAN mode.

7. Set the calibrator output to 50.0mV (70mV maximum).

8. Using the arrow keys, adjust the displayed value to equal the calibrator output.

Calibration of the Cold Junction Temperature

Calibration procedure:

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1. Change the millivolt source calibrator to thermocouple mode with internal cold junction compensation. Change the copper wire with the correct thermocouple extension wire

2. Set the calibrator to a typical temperature level.

3. Use the Versapro Enter key to advance to the CJ Adjustment display.

4. Using the arrow keys, adjust the displayed value to equal the calibrator input.

Ref to the following tables for the valid range of thermocouple inputs that can be used to calibrate the cold junction compensation.

Table 16 Thermocouple Calibration Values

B

E

J

K

N

R

T/C type Minimum Value

°F (°C)

800 (426)

-454 (-270)

32 (0)

32 (0)

32 (0)

300 (150)

Maximum Value

°F (°C)

3000 (1800)

1832 (1000)

1300 (900)

2300 (1200)

2300 (1200)

3000 (1800)

S

T

300 (150)

32 (0)

3000 (1800)

700 (350)

The usable ranges for the thermocouple types are shown in the following table. If it is desirable to have a higher accuracy over a specific operating range then the input should be calibrated over that range.

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Table 17 Usable Thermocouple Range (°F)

T/C type Minimum

Value (°F)

Maximum

Value (°F)

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R 300

T -380

3210

3210

755

* Due to the extreme non-linearity of low level signals, using type R and S below 300° F is not recommended.

Calibration of the Probe Millivolt Input

Calibration procedure:

1. Connect terminals TB-B 3, 4 to an isolated, stable millivolt source calibrator using standard copper wire, 20 AWG is sufficient. A maximum output of 2000 mV is required.

2. Set the calibrator output to 0.00 mV.

3. Activate the calibration mode by entering the SETUP menus, selecting the Calibration menu and changing Calibration IN - NO to YES.

4. Use the Enter key to select the MV ZERO mode.

5. Using the arrow keys, adjust the process value to equal the calibrator input.

6. Press the Enter key to select the MV SPAN mode.

7. Set the calibrator output to the required millivolt span (2000 mV maximum).

8. NOTE: The displayed number will change in resolution. The millivolt value will show the tenths digit if the measured value is less than 1000 mV. Above 999.9 mV the display will shift to whole numbers. Use the arrow keys to adjust the process value to equal the calibrator output.

Preparing for Analog Output Calibration

The same calibration procedure can be used for either output channel. For the CAL

OUTPUT mode, the following keys perform the described functions:

UP ARROW

DOWN ARROW

RIGHT ARROW

Increases the value of the flashing digit.

Decreases the value of the flashing digit.

Shifts the flashing digit to the right.

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LEFT ARROW Shifts the flashing digit to the left.

ENTER Advances to next calibration value and saves the calibration changes.

SETUP

Calibration procedure:

Exits the calibration mode.

1. Connect terminals TB-B 5, 6 (or 7, 8) to a multimeter such as a Fluke 77. Select the milliamp measurement range and verify that the test leads are plugged into the milliamp jack and common on the multimeter.

2. Activate the calibration mode by entering the SETUP menu, selecting the Calibration menu, press the ENTER key until CAL OUTPUT - NO is displayed.

3. Change the NO prompt to YES using the UP arrow key.

4. Press the ENTER key to select the OUTPUT 1 MIN mode. If OUTPUT 2 is required, continue pressing the ENTER key until OUT 2 MIN is displayed.

5. Using the UP or DOWN arrow keys, adjust the displayed number from 0 to 9. Press the

RIGHT or LEFT arrow keys to select the adjustment sensitivity. Adjust the displayed value until the multimeter indicates the desired minimum output. This is typically set for 4 mA (cal factor ~ 800), but this level can be adjusted to 0mA (cal factor ~ 0).

6. Press the ENTER key to select the OUTPUT 1 SPAN mode. If OUTPUT 2 is required, continue pressing the ENTER key until OUTPUT 2 SPAN is displayed.

7. Using the arrow keys as explained in step 5, adjust the output to read 20mA on the multimeter. A typical cal factor for 20mA is 3200. The maximum cal factor is 4095.

8. Press the SETUP key to save the calibration values and exit the calibration routine.

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Communications

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Modbus

The MODBUS protocol describes an industrial communications and distributed control system (DCS) that integrates PLCs computers, terminals, and other monitoring, sensing, and control devices. MODBUS is a Master/Slave communications protocol, whereby one device, (the Master), controls all serial activity by selectively polling one or more slave devices. The protocol provides for one master device and up to 247 slave devices on a half duplex twisted pair line. Each device is assigned an address to distinguish it from all other connected devices.

The VersaPro recognizes three Modbus RTU (Remote Terminal Unit) commands. These are: read single I registers (command 4), read a single H register (command 3), and preset a single H register (command 6)

In the RTU protocol sends data in 8-bit binary characters. Message characters are transmitted in a continuous stream. The message stream is setup based on the following structure:

Number of bits per character:

Data bits (least significant first) 8

Parity 0 (no bits for no parity)

Error Checking CRC (Cyclical Redundancy Check)

In Modbus mode, the VersaPro can be only be configured for the ‘none’ parity option.

The instrument never initiate communications and is always in the receive mode unless responding to a query.

RTU Framing

Frame synchronization can be maintained in RTU transmission mode only by simulating a synchronous message. The instrument monitors the elapsed time between receipt of characters. If three and one-half character times elapse without a new character or completion of the frame, then the instrument flushes the frame and assumes that the next byte received will be an address. The follow command message structure is used, where T is the required character delay. Response from the instrument is based on the command.

T1,T2,T3 ADDRESS FUNCTION DATA CHECKSUM T1,T2,T3

8-BITS 8-BITS N X 8-BITS 16-BITS

Address Field

The address field immediately follows the beginning of the frame and consists of 8-bits.

These bits indicate the user assigned address of the slave device that is to receive the message sent by the attached master.

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Each slave must be assigned a unique address and only the addressed slave will respond to a query that contains its address. When the slave sends a response, the slave address informs the master which slave is communicating.

Function Field

The Function Code field tells the addressed slave what function to perform. MODBUS function codes are specifically designed for interacting with a PLC on the MODBUS industrial communications system. Command codes were established to manipulate PLC registers and coils. As far as the VersaPro is concerned, they are all just memory locations, but the response to each command is consistent with Modbus specifications.

The high order bit in this field is set by the slave device to indicate an exception condition in the response message. If no exceptions exist, the high-order bit is maintained as zero in the response message.

Data Field

The data field contains information needed by the slave to perform the specific function or it contains data collected by the slave in response to a query. This information may be values, address references, or limits. For example, the function code tells the slave to read a holding register, and the data field is needed to indicate which register to start at and how many to read.

Error Check Field (CRC)

This field allows the master and slave devices to check a message for errors in transmission.

Sometimes, because of electrical noise or other interference, a message may be changed slightly while it is on its way from one device to another. The error checking assures that the slave or master does not react to messages that have changed during transmission. This increases the safety and the efficiency of the MODBUS system.

The error check field uses a CRC-16 check in the RTU mode.

The following is an example of a function 03 call for timer setpoint value (TSETPT) at memory location 03. The value returned by the instrument is the hex value 1E (30 seconds).

Transmit from Host or Master

Address Cmd Reg

HI

Reg

LO

Count

HI

Count

LO

CRC

HI

CRC

LO

01 03 00 03 00 01 74 0A

Response from Versapro

Address Cmd Byte

Count

HI

01 03 00

Byte

Count

LO

Data

HI

Data

LO

CRC

HI

CRC

Lo

02 00 1E 38 4C

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Note that all the values are interpreted as hexadecimal values. The CRC calculation is based on the A001 polynomial for RTU Modbus. The function 04 command structure is similar to the 03 structure.

The following is an example of a function 06 call to change the remote setpoint (RSETPT) to 200 (2.00%). The response from the instrument confirms the new value as being set.

Transmit from Host or Master

Address Cmd Reg

HI

Reg

LO

Data

HI

Data

LO

CRC

HI

CRC

LO

Response from Versapro

Address Cmd Reg

HI

Reg

LO

Data

HI

Data

LO

CRC

HI

CRC

LO

The Versapro will respond to several error conditions. The three exception codes that will generate a response from the instrument are:

01 – Illegal Function

02 - Illegal Data Address

03 – Illegal Data Value

04 – Slave Device Failure

The response from the Versapro with an exception code will have the most significant bit of the requested function set followed by the exception code and the high and low CRC bytes.

MMI Message Protocol

The basic Marathon Monitors message protocol format is shown below.

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As indicated, the MMI or proprietary mode allows communication using the 10PRO ‘A’ command protocol or the ‘U’ block protocol.

The following command set applies to the ‘A’ command and is used for the Versapro and other 10PRO type instruments such as temperature controller slaves. The command set is sent by a master to a 10PRO slave instrument. These commands can also be used by any device such as a computer communicating with instruments via an instrument network. The commands that are supported are shown in the following table.

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Table 18 10Pro / 10Pro-T Command Set

Dew Point

COMMAND

LETTER

p (low case) o (low case) i (low case) h (low case)

I (upper case as in

Instrument)

J (upper case)

Process ( temperature) Timer

Read Auto / Manual mode

Read Remote / Local

Read Remote Process

Setpoint

Read Auto Process

Setpoint

Update Process Setpoint

Temporarily

Update Process Setpoint

Permanently

Read Actual Process

Same

Returned Value

A = auto, B = manual

Same A = local, B = remote

Read Remote Time

Setpoint integer decimal number

Read Auto Time Setpoint integer decimal number

Update Time Setpoint

Temporarily integer decimal number

Update Time setpoint

Permanently

Read Remaining Time integer decimal number integer decimal number l (lower case as in limits) m (low case)

P (upper case)

Read % Output

Update Auto/Manual mode

Read Time control byte

Same integer decimal number

A = auto, B = manual

The following are examples of commands and responses using the 10Pro type command set.

The first row in each table shows the ASCII characters of the command as they would appear if monitored on the serial port. The second row in each table is the hexadecimal translation of the characters transmitted on the serial port. These values must be known to calculate the checksum.

This is the command and response for reading the actual process value of a 10Pro type slave instrument. In this example the 10Pro instrument address is 2 and the return value is 0071.

This could be 71 degrees. 0.71% DEWPT, 7.1 degrees dewpoint, or 0.71% oxygen depending on the process and the instrument settings. Other parameters and scaling are available if the linear inputs are selected. In general the number that is returned is the number displayed on the instrument. Decimal point information is assumed.

Add

2

Transmit from Host or Master

Prefix Cmd

A l

Delim LRC

<NULL> <HEX 1F > <EOT>

Add Prefix Cmd

Response from 10Pro

D1 D2 D3 D4 Delim LRC

0x06 0x32 0x41 0x6C 0x30 0x30 0x37 0x31 0x00 0x1F

Here is an example of a request and response for the local setpoint of the instrument in

Automatic mode. The response indicates that the instrument’s address is 2 and the local setpoint is 1500.

Transmit from Host or Master

Add

2

Prefix Cmd

A h

Delim LRC

<NULL> <HEX 1B > <EOT>

0x04

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Response from 10Pro

Add Prefix Cmd D1 D2 D3 D4 Delim LRC

<ACK> 1 5 0 0 <NULL>

0x06 0x32 0x41 0x68 0x31 0x35 0x30 0x30 0x00 0x19

Here is an example that shows how the HOST changes the instrument’s remote set point.

The instrument’s address is 15. The HOST has sent a command to update the remote setpoint with 1450. The instrument responds by echoing the command.

Transmit from Host or Master

0x04

Add Prefix Cmd

F A I

D1 D2 D3 D4 Delim LRC

0x46 0x41 0x49 0x31 0x34 0x35 0x30 0x00 0x4E

<EOT>

0x04

Add Prefix Cmd

Response from 10Pro

D1 D2 D3 D4 Delim LRC

0x06 0x46 0x41 0x49 0x31 0x34 0x35 0x30 0x00 0x48

Instrument Type ‘U’ Command Set

The MMI (Marathon Monitors Inc.) command set supports the extensive capabilities of the

Dualpro the 10Pro-E and the Versapro. The command set consists of the characters shown in the following table.

<EOT>

0x04

Table 19 MMI Command Set

Update Read Description

X x

Not Allowed *

Read / Writer Table

Parameters

Read Block Transfer

‘X’ Command

The ‘X’ command allows almost unlimited access to all the instrument parameters. The ‘X” command accesses the various parameter tables in the instrument. A typical parameter table for most Marathon instruments has 240 parameters numbered consecutively from 0 to

239 (0 – 0xEF). Instruments such as the Dualpro have many tables (0 – 31), where each table has 11 blocks or more.

The Versapro, 10Pro-E, and Version 3.5 Carbpro have only table 0. The table value is assumed to be 0 and the parameter is addressed directly with the possible range of 0 to 71.

These number correspond with the decimal numbers in the Versapro Memory Map table.

To READ a data value from a table / parameter number in the instrument, use the following format:

AUx (Table # Parameter #) <delimiter> <checksum> <EOT>

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Here is an example of a request and response for the instrument’s proportional band setting in table 0, parameter 10 (0x0A). The instrument address is 1. The data value that is returned by the instrument is hexadecimal 0014 or 20.

Transmit from Host or Master

Add

1

0x31

Prefix

U

0x55

Cmd x

0x78

Table #

00

Par #

0A

Delim

NULL

0x30 0x30 0x30 0x41 0x00

LRC

<HEX 6D >

0x6D

Add Prefix Cmd Table

#

Par

#

Instrument Response

Data

Delim

D1 D2 D3 D4 Delim

EOT

0x04

LRC

0x06 0x32 0x55 0x78 0x30

0x30

0x30

0x41

0x24 0x30 0x30 0x31 0x34 0x00 0x4A 0x04

The response from the instrument includes the ‘$’ character. This characters acts as the data delimiter, which separates the parameter data from the parameter address.

Here is an example of a request and response for the instrument’s Alarm 1 value in table 00

(0x00) parameter 06 (0x06). The instrument address is 1. The data value that is returned by the instrument is 50 (0x32). The actual value is 0.50 where the decimal point is implied by the process.

Transmit from Host or Master

Add Prefix Cmd Table # Par # Delim LRC

0x31 0x55 0x78 0x31

0x30

0x31

0x33

0x00 0x1A 0x04

Add Prefix Cmd Table

#

Response from Instrument

Par

#

Data

Delim

D1 D2 D3 D4 Delim LRC

0x06 0x31 0x55 0x78 0x30

0x30

0x30

0x36

0x24 0x30 0x30 0x33 0x32 0x00 0x39 0x04

The parameter write command uses the following format:

AUX (Table # Parameter #) $ data <delimiter> <LRC> <EOT>

To write a value to the instrument for a specific parameter use the uppercase X. To read a specific parameter from the instrument, use the lowercase x.

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Here is an example of a parameter write command and response for data in table 00 (0x00) parameter 06 (0x06). The instrument address is 1. The data value that is written to the instrument is 0000 (0x0000).

Transmit from Host or Master

Add Prefix Cmd Table

#

Par

#

Data

Delim

D1 D2 D3 D4 Delim LRC

0x31 0x55 0x58 0x30

0x30

0x30

0x36

0x24 0x30 0x30 0x30 0x30 0x00 0x1E 0x04

Response from Instrument

Add Prefix Cmd Table

#

Par

#

Data

Delim

D1 D2 D3 D4 Delim LRC

0x06 0x31 0x55 0x58 0x30

0x30

0x30

0x36

0x24 0x30 0x30 0x30 0x30 0x00 0x18 0x04

The parameters for the Versapro are listed in the manual appendix. This listing includes the parameter name, number, and a short description that includes bit and byte mapping information.

Block Commands

Block transfer commands are used to read and write data in a group of 24 words. The

Versapro has only three blocks in table zero. The block transfer command has to identify the table as well as the block.

A block read command format is shown below.

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A U * tt bb D L E

Dew Point

(E)End of Transmission (EOT) HEX(04)

(L) LRC is the result of an XOR function performed on all previous character in the messeage.

(D) Delimter marks the end of DATA and signals the up coming EOT character.

NUL HEX(00) or Backspace HEX(08)*

*If LRC was going to be an EOT HEX(04) then D =

HEX(08).

(bb) Block number 0 - 2

(tt) Table number (HEX)

(*) Block Read command character

(I) Instruement Prefix: U = Dualpro/10Pro-E/V3.5/

Versapro.

(A) Address of instrument.

Figure 9 Block Read Command Format

The reply to a Block read request follows.

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A U * tt bb $ ddd-------ddd CC D L E

Dew Point

(E)End of Transmission (EOT) HEX(04)

(L) LRC is the result of an XOR function performed on all previous character in the messeage.

(D) Delimter marks the end of DATA and signals the up coming EOT character.

NUL HEX(00) or Backspace HEX(08)*

*If LRC was going to be an EOT HEX(04) then D =

HEX(08).

(CC) MOD 256 checksum of data characters ASCII values in two (2) HEX digits.

Ninety-six (96) HEX digits of data, four (4) digits, (2) bytes, (24) parameters

($) Data separator

(bb) Block number (HEX)

(tt) Table number (HEX)

(*) Block Read command character

(I) Instruement Prefix: U = Versapro instrument prefix.

(A) Address of instrument.

Figure 10 Block Read Response Format

The following is an example is for a block request from the Host and a reply from the instrument. The Host sends the command:

1U*0000<00>N<04><06>

Where the instrument address is ‘1’, the instrument type is ‘U’, the table and block are both zero (TTBB), and the delimiter, LRC and EOT follow.

The instrument responds with the string shown in the following table.

Table 20 Sample Block Response

Hex ASCII

Address 1 31

Command * 2A

Register 0000 30 30 30 30

Delimiter $ 24

Parameter 1

Parameter 2

Parameter 3

Parameter 4

C11C

00E5

8112

0096

43 31 31 43

30 30 45 35

38 31 31 32

30 30 39 36

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Parameter 5

Parameter 6

Parameter 7

Parameter 8

Parameter 9

Parameter 10

Parameter 11

Parameter 12

Parameter 13

Parameter 14

Parameter 15

Parameter 16

Parameter 17

Parameter 18

Parameter 19

Parameter 20

Parameter 21

Parameter 22

Parameter 23

Parameter 24

0096

00C8

03B6

07D0

0000

0C00

03E8

03E8

0000

0000

0000

0000

0060

1C25

00F3

3C69

0001

03E8

0000

3D62

30 30 39 36

30 30 43 38

30 33 42 36

30 37 44 30

30 30 30 30

30 43 30 30

30 33 45 38

30 33 45 38

30 30 30 30

30 30 30 30

30 30 30 30

30 30 30 30

30 30 36 30

31 43 32 35

30 30 46 33

33 43 46 39

30 30 30 31

30 33 45 38

30 30 30 30

33 44 36 32

MOD 256 BF 42 46

Delimiter 00 00

Dew Point

Note that the MOD 256 is the 256 modulus of the sum of the ASCII values of the parameters. The delimeter and LRC are calculated as described in a previous section.

MMI Error Codes

The Marathon protocol for the Versapro has three error codes that can be generated by the instrument: E1 = Incorrect LRC detected on received message, E2 = Invalid command detected, and E3 = Invalid table or parameter address.

The format for the error message is

<NAK> Error Code DEL LRC <EOT>

Where <NAK> is the hexadecimal value 15 followed by the ASCII characters for the appropriate error code. The delimiter and LRC are calculated the same as for a normal message. The EOT (hexadecimal 04) end every message in the MMI protocol.

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Process Calculation

Dew Point Process Control

4238.7

Dew Point

Dewpoint = ----------------------------------

9.55731 - log10(E / (Tk x 0.0215)

Where:

E = probe millivolts + mv offset, Tk = probe temperature in degrees Kelvin.

NOTE:

This calculation is only valid for Endothremic Rx gas in a state of equilibrium. The equation will not work for a dew point calculation on Exothermic gases.

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Troubleshooting Questions

Dew Point

This section is organized alphabetically by the functional name of various instrument operations and features. Some explanations may be listed in more than one category since the problem can be approached from several different points of view. Each problem is presented as a question for typical problems that may be encountered. In most cases the problem can be resolved by changing a setup parameter in the instrument.

Analog Inputs

How come the display flashes HHHH or LLLL when I try to read a signal at input A or input B in linear mode?

There are possibly two reasons; the decimal point setting in the Calc menu has to be adjusted for the maximum signal level to be read or the signal level has exceeded the range of the input channel. Channel A is set up primarily for thermocouple levels from –10mV to 70mV.

Channel B is set up for oxygen sensor millivolt ranges of 0 to 2000 mV. The display decimal point setting will not truncate the input value, it just increases the resolution of the input signal. If the value is within the input range of the channel but greater than or less than the possible display setting then the limit warnings will flash on the display.

I am trying to offset the temperature using the offset and scaling number in the Input menu but the temperature does not change.

The input offset and scaling numbers for inputs A and B only work if either Linear A or

Linear B are selected as the process source in the Control Menu. If it is necessary to offset the temperature slightly it is possible to do this by changing the cold junction trim adjustment in the Input Calibration menu. It is not recommended that the actual linear calibration values for input A are changed.

Control Outputs

I have a dual contact control mode selected but my second contact does not work.

When a dual control mode is selected it is necessary to also set the high percent output

(HIPO) and low percent output (LOPO). In single time proportioning, the default mode, the

HIPO is 100 and the LOPO is 0. When a dual mode is selected it is necessary to change the

LOPO to –100. In the case of DEWPT control it is typically required to control gas and air.

The first control contact would be connected to the gas solenoid and the second control contact would be connected to the air solenoid. The gas solenoid would be turn on all the time when the control output goes to 100%. Likewise the air solenoid would be on all the time if the control output was –100%.

When would I change my HIPO or LOPO settings to something other then the 100% or –100%?

These values rarely have to be changed but one case that requires it is when the control actuator is not acting an expected linear fashion. An example would be an SCR driving a heater. If the SCR is not actually turning on until the control signal is at 20% and stops increasing at 80% then the linear response of the actuator is only between 20% and 80%. If the controller assumes the full output range of 0 to 100% then a large delay in process reaction will drive the reset function in the PID control calculation into oscillation. It would be necessary to set the LOPO to 20% and the HIPO to 100% to achieve stable control.

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Digital Communications

How come I have communications problems with an instrument address following a

Versapro address setting.

If the timer function has been enabled and the Versapro host protocol is set to ‘Prop’ for the

Marathon protocol, the instrument will take the next host address setting to respond with the timer parameters. The problem can be corrected by turning of the timer function in the

Control menu or setting to next instrument address to Versapro host address + 2.

Display Functions

How come the display flashes HHHH or LLLL when I try to read a signal at input A or input B in linear mode?

There are possibly two reasons; the decimal point setting in the Calc menu has to be adjusted for the maximum signal level to be read or the signal level has exceeded the range of the input channel. Channel A is set up primarily for thermocouple levels from –10mV to 70mV.

Channel B is set up for oxygen sensor millivolt ranges of 0 to 2000 mV. The display decimal point setting will not truncate the input value. If the value is within the input range of the channel but greater than or less than the possible display setting then the limit warnings will flash on the display.

How come the process values will not cycle on the display when I press the Enter key?

The display will not cycle through the process values if there is an active alarm. Press the

Enter key to see any active alarms. If multiple alarms are active it will be necessary to press the UP or DOWN keys until all of the alarms have been displayed. It is necessary to clear these alarms before the display will cycle by pressing the Enter key.

Probe Care

How can I clear the Probe Fault alarm?

The probe fault can only be cleared with a successful test. Several ways to force this are to start and then quickly stop the probe tests or set the test criteria above the last test data collected during the failure.

I keep getting the Probe Fault alarm but do not know what the problem is?

A probe fault can occur if one of several parameters exceed defined limits. These parameters are set in the Probe Care menu. For the DEWPT, oxygen, and dew point processes the probe impedance and probe impedance recovery time are tested when the ‘res’ or ‘both’ modes are selected in the probe menu. If the Probe Impedance Limit (Kohm) or

Impedance Recovery Time limit (seconds) are exceeded then the probe fault condition is set.

The ‘burnoff’ or ‘both’ test modes for DEWPT and dewpoint are compared to a burnoff test recovery time setting (seconds). If the mV output of the sensor measured prior to the test does not return to previous level within the recovery time setting then the probe fault condition is set.

The ‘verify’ or ‘both’ test modes for oxygen measure the oxygen during the introduction of a known test gas. If this measurement does not fall within the limits of the standard verification gas setting and the allowed tolerance then the probe fault will be set. Most of the probe test results are displayed in the display cycle by pressing the Enter key but if a

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fault has occurred this function is disabled so that multiple alarms may be viewed. It is necessary to go to the Info menu to view the probe test measurements and compare these data to the probe test settings.

How come I am failing the recovery time limit?

Check the filter time for the temperature or millivolt input. A small filter time will allow the instrument to update the measured values faster and give a more accurate recovery time.

The recovery time setting can no be shorter than the filter time setting. Both are set and displayed in seconds.

How come the probe test will not start?

One of the probe test parameters is minimum test temperature. The default of this temperature is 1400. If the measured temperature is below this value the test will not run.

This minimum temperature setting is limited by the minimum temperature required for the sensor to operate. This limit is typically 1000 to 1100 mV. Trying to do a probe test below these temperatures or with no process atmosphere present will not produce any reliable information.

Timer Function

How come I can not enter a timer setpoint.

Two things have to be set for the timer to work; the timer has to be enabled in the Control

Menu, and a timer alarm function has to be selected for alarm 1 or alarm 2 but not both alarms at the same time. Only when these conditions have been met will the instrument accept a timer setpoint.

How come I can not start a timer function when the Input Event is set to Start and

activated?

Make sure all of the conditions explained in the first question of this time section have been met.

Why is there a delay between the Timer display changing to zero and the End alarm coming on?

The timer is counting in milliseconds but only displays whole seconds. When the display first changes from 1 to 0 it actually changes to 0.99. It continues to count down for the remaining milliseconds until the timer reaches zero at which point it turns on the End alarm.

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Versapro Monitor Mode

Dew Point

The Versapro’s internal EEPROM can be reprogrammed when placed in Monitor Mode.

This mode allows the user to perform checks and set default conditions in the instrument by using a RS232 to RS485 converter and the popular Windows

 program HyperTerminal.

It is necessary to enter this mode when a CPU has been re-programmed or if a checksum fault has occurred in EEPROM.

The user can also use advanced features of Monitor Mode such as status check, read RAM and FLASH memory, write to RAM memory, load FLASH defaults to RAM, load EEPROM defaults from RAM to EEPROM, or write from EEPROM into RAM.

Prepare for Connection

Make sure you have recorded all the operational parameters of the instrument before you change the EEPROM values. These parameters will include the thermocouple type, alarm functions, and probe care settings. For the controller version of the Versapro this will also include control and PID settings as well. Note the instrument calibration settings for the two analog output channels by going into the SETUP mode, selecting CAL OUT – Yes and recording the offset and span values shown for each channel. Advance to the each parameter by pressing the <Enter> key. Press <Setup> to return to the process mode.

How to Connect

The Versapro has a RS485 half-duplex port located on terminals TB-B 13 and 14, where 13 is the +RS485 connection and 14 is the –RS485 connection.

Insure your converter is plugged into the serial port of your computer. Insure that your converter is configured as a half-duplex (two wire) output and not as a full-duplex (four wire) output.

Apply power to the instrument and observe that it is operating in normal process mode where the process name is displayed in the center LCD display.

NOTE

Your version of HyperTerminal may be different then the steps outlined in this procedure.

The basic information provide here will apply to any configuration. Accept the setup defaults if you are not sure about a specific feature that is not addressed here.

When HyperTerminal starts up it asks for a name of a new connection. Enter a name that you can associate with the Versapro setup.

The ‘Connect To’ window will then appear.

Make the following selections in the Connect To window;

Connect using: (select the comm port the RS485 is connected to)

Press the ‘OK’ button.

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In the ‘Port Settings’ window that appears next, make the following selections;

Bits per second: 19200

Data bits: 7

EVEN bits:

Flow control: None

Select the File \ Properties \ Settings tabs and make the following selections;

Select the ‘Terminal Keys’ button

Select the ‘Ctrl+H’ button

Set ‘Emulation’ to ANSI

Set ‘Telnet terminal ID’ to ANSI

Set ‘Backscroll buffer lines’ to 500

Click on the ASCII Setup… button;

Set ‘Line delay’ to 25 msec

Set ‘Character delay’ to 0 msec

Click on the ‘OK’ button to escape the Connections window.

HyperTerminal will now be connected to the comms port waiting for serial data from the

Versapro.

Start Monitor Mode

At the Versapro press and hold the <REM> and <Enter> keys. Hold these keys until the center display changes to "MONITOR MODE”, (about 5 seconds). The instrument will send a prompt to the HyperTerminal screen that should look like figure 1. If the Versapro is already in Monitor Mode it may only have the Power light on with no other display. Cycle power on the instrument while connected to see the “Marathon Monitors , Inc.” prompt.

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Figure 11 Initial Prompt Screen

The following table lists the commands that are available in Monitor mode.

Command

D

Command Description

Displays 16 rows by 16 bytes of memory

J

K

Displays all values in EEPROM

Programs EEPROM for RAM values

L

S

W

X

Z

Loads RAM EEPROM area with FLASH defaults

Displays status of processor

Writes a byte from EEPROM to RAM

EEPROM mirror or writes data to RAM.

Exits Monitor mode

Resets processor idle counter

The Versapro is placed into Monitor mode when the <Enter> and <Rem> keys on the instrument are pressed simultaneously and held for about 5 seconds. The LCD display will display the prompt ‘MONITOR MODE’ and the LED display will be blank. The instrument also sends banner and prompt character to the HyperTerminal screen. The following figure shows this display.

At the ‘>’ prompt type any of the above commands.

At this point the instrument is not performing any process or control functions but is only waiting for Monitor mode commands.

‘D’ Display Command

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Marathon Monitors Inc. Dew Point

The ‘D’ command is a multiple character command that displays a block of memory. The command format is D xxxx <Enter>. The xxxx is any memory location in four character hexadecimal format. The <Enter> is pressing the computer keyboard <Enter> key.

If no memory starting address is entered the Monitor assumes a starting location of 0000.

Each line of the display starts with the first memory address followed by 16 bytes of data stored in the following 16 memory locations. 16 lines are displays, showing 255 bytes of data.

The range of memory must be between 0000 and FFFF. The display will wrap to the beginning of the memory if it exceeds the limit of the FFFF location. Some of the zero page memory values will change when the Monitor mode is started. This command is useful for looking at data in upper memory that stays relatively static.

‘L’ Write FLASH to RAM Defaults

The ‘L’ command is the first command used to program the EEPROM with default values in

FLASH. The EEPROM is written for a RAM area that mirrors the structure of the

EEPROM. To initialize the EEPROM it is first necessary to write the default values from

FLASH into the RAM mirror.

This is a single character command that is sent to the instrument when the character is typed at the HyperTerminal display and the keyboard <Enter> key is pressed. The computer will display all the values that have been written into the RAM area. See the ‘K’ command for the next step in programming the EEPROM.

‘K’ Write RAM to EEPROM

The ‘K’ command is a single character command that copies the values in the RAM mirror into the EEPROM. The EEPROM is completely erased before any values are written. There is no display that is generated while this function is executed. It is necessary to wait about 5 seconds for the display prompt (>) to return before another command is issued.

‘J’ Display EEPROM Values

This is a single character command that displays all of the EEPROM values in the same format as the ‘D’ command.

‘S’ Status Display

This is a single character command that displays the status of the processor. This command is helpful when trying to determine what fault may have caused a reset. The display will show any fault codes and a thumb twiddler value. This value is an idle counter for the processor and should be greater than zero for normal operation.

‘W’ Write RAM with EEPROM or Data Values

The ‘W’ command is a multiple character command that writes a byte from EEPROM to

RAM memory if the RAM address is within the range of the EEPROM - RAM image.

Otherwise if the RAM address is an address is outside the EEPROM image address it will

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Marathon Monitors Inc. Dew Point

write input data to a RAM address. The formate is W <addr> for the first condition and W

<addr> <data> for the second condition where both the address and data are four character hexadecimal values.

‘X’ Exit Command

This is a single character command the turns off the Monitor mode, resets the processor, and returns the processor to normal process mode. If the processor does not return to normal mode following this command, check the status for any fault conditions.

Viewing Status and Memory

The next figure shows the displays for the status command and the memory display command. The status command will show any faults or resets that have occurred in the instrument. The Thumb Twiddler number is a count of idle time for the processor. The reset number for this is 3000 (‘Z’ command). This number should never reach zero.

The ‘D’ command is followed by the start of the memory locations to be displayed. In this case the EEPROM memory block is being displayed starting at hexadecimal address 0800.

Figure 12 ‘S’ and ‘D’ Commands

Loading Default Values

The most common use of the Monitor Mode is to re-set or load the processor’s internal

EEPROM with default values and re-calculate the EEPROM checksum. This is done with a series of commands starting with the ‘L’ command.

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The instrument holds default operational parameters in FLASH. This area of memory is mapped the same way the EEPROM memory is. The instrument also uses a pre-defined area in RAM to change and then copy data into EEPROM. This RAM area is also mapped the same as the EEPROM. It is necessary to copy the FLASH values to the RAM area first using the ‘L’ command.

At the > prompt, type in the character ‘L’ and press the Enter key. This command will tell the instrument to load the RAM area with default values from the FLASH memory.

A series of character lines will print down the screen followed by another prompt. At the prompt, type in the character ‘K’ and press Enter. This command will tell the instrument to load the EEPROM from the RAM image that has just been programmed.

The screen will advance one line and display the prompt. At the prompt, type in the character ‘X’ and press Enter. The ‘X’ command causes the instrument to exit monitor mode, resets the processor, and returns to operation mode. This sequence is shown in the following figure.

Figure 13 ‘L’ and ‘K’ Commands

At the prompt, type in the character ‘X’ and press Enter. The ‘X’ command causes the instrument to exit the Monitor Mode, reset, and return to operation mode. Check the instrument parameter settings and verify the input and output calibration settings.

What if an error occurs

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If you receive check sum errors following the ‘L’ or ‘K’ commands, retry these commands.

If this does not resolve errors during the RAM or EPROM procedures then the instrument memory maybe damaged. The instrument should be returned to Marathon Monitors , Inc. for testing and possible repair.

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Technical Specification

Dew Point

Environmental ratings

Panel sealing:

Operating temperature:

Relative humidity:

Atmosphere:

Instruments are intended to be panel mounted. The rating of panel sealing is IP64.

0 to 55 o

C. Ensure the enclosure provides adequate ventilation.

5 to 95%, non-condensing.

The instrument is not suitable for use above 2000m or in explosive or corrosive atmospheres.

Equipment ratings

Supply voltage:

Supply frequency:

Power consumption:

Relay 2-pin (isolated):

100 to 240Vac -15%, +10%, or optionally:

48 to 62Hz.

15 Watts maximum.

Maximum: 264Vac, 2A resistive. Minimum: 12Vdc,

100mA.

Relay changeover (isolated): Maximum: 264Vac, 2A resistive. Minimum: 6Vdc, 1mA.

Over current protection: External over current protection devices are required that match the wiring of the installation. A minimum of 0.5mm

2

Relay outputs:

Low level I/O:

DC output (Isolated):

Fixed digital inputs: or 16awg wire is recommended. Use independent fuses for the instrument supply and each relay output. Instrument supply: 85 to 264Vac, 2A.

Triac outputs: 1A.

All analog input and output connections are intended for low level signals less than 24VDC.

0 to 20mA (650

Ω max), 0 to 10V (using a 500Ω dropping resistor).

Contact closure. (common to internal 5VDC source.)

DC or PV input:

Transmitter supply:

Digital Comms:

As main input plus 0-1.6Vdc, Impedance, >100M

Ω.

(isolated.)

30Vdc at 20mA. (isolated.)

EIA-485 half duplex. (isolated).

General

Thermocouple input:

Millivolt input :

Type B, K, R, and S accuracy after linearization +/- 1 deg F

0 to 2000 millivolts +/- 0.1 millivolt

Cold junction compensation: 0 to 60°C +/- 1 deg F

Calibration accuracy: The greater of +0.2% of reading, +1 LSD or +1 o

C.

Calculations:

Accuracy:

Power input to signal inputs

Power input to communications

Percent DEWPT 0 – 2.55% (no CO compensation)

Dewpoint -99 – 212 °F (no hydrogen compensation)

(Small oxygen concentrations can be measured by changing the exponent setting.)

+/- 1 of LSD of process value.

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Communications port:

Protocol:

Baud rates:

Parity:

Control Mode

RS-485 Half Duplex Only

10Pro, MMI block transfer, or Modbus RTU

1200, 2400, 4800, 9600, 19.2K

Even, odd, or None

Time Proportioning Single Contact Direct

Time Proportioning Single Contact Reverse

Time Proportioning Dual Contact Direct

Time Proportioning Dual Contact Reverse

Time Proportioning Complement Contact Direct

Time Proportioning Complement Contact Reverse

Dew Point

On / Off Reverse

On / Off Dual Direct

On / Off Dual Reverse

On / Off Complement Direct

On / Off Complement Reverse

Alarm Type (both Alarm 1 and 2)

High Limit Temp

Input Fault (mV or Thermocouple)

Time (start timer no conditions)

Start (guaranteed timer at set point)

Soak (guaranteed timer run in band)

Digital Event Input (isolated contact closure)

Manual/Auto

Local/Remote

Start

Hold Timer

Acknowledged End

Electrical safety (pending approval)

Standards: EN 61010, Installation category II, pollution degree 2.

Installation category II: Voltage transients on any mains power connected to the instrument must not exceed 2.0 kV.

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Pollution degree 2: Conductive pollution must be excluded from the cabinet in which the instrument is mounted.

Environmental Conditions

Operating Temperature

Storage Temperature

Operating and Storage Humidity

-20 °C to 65 °C (-4 to 176 F)

-40 °C to 85 °C (-40 to 185 F)

85% max relative humidity, noncondensing, from –

20 to 65°C

Electromagnetic Compatibility (pending approval)

Immunity

Electromagnetic RF fields EN 61000-4-3

±8 kV air

Level 2:

±4 kV contact

Level 3: 10 V/m

MHz MHz

RF conducted interference EN 61000-4-6

±1 kV I/O

Level 3:

±2 kV power

Level 3: 10 V/rms

150 MHz

Power Freq Magnetic Fields EN 61000-4-8 30 A/m, x y z planes

Voltage Variations

61000-4-5

±1kV L-L, ±2kV L-PE

/ 0°,

EN 61000-4-11 70% of operating voltage

0.5 cycles/10ms

Emissions

RF Emissions

Conducted Emissions

CSIPR Class B

CISPR Class B

Harmonic Current Emissions EN 61000-3-2

Note: Specifications may change without notification.

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Versapro Memory Map

Dew Point

NOTE: Modbus refers to the hexadecimal address location. These parameters are formatted as unsigned 16 bit integers. Any real number such as temperature can be evaluated as a signed number, other parameters are bit mapped words that must be evaluated as single bits are bit groups.

BLOCK 0

HEX

00

01

03

05

06

07

DEC PARAMETER DESCRIPTION

0

1

Not used

RSETPT

3 TSETPT

04 4

5

6

7

PROC

TIME

ALARM1

ALARM2

READ/WRITE

READ ONLY

Remote setpoint sent to the instrument from the Host port. This number has to be scaled to the range of the displayed process value based on the decimal point and exponent settings of the instrument.

Range = -999 to 9999

Default = 0.000

For example: If the process = oxygen, display decimal point = 2, and exponent = 6, as remote setpoint of 1234 would be interpreted and displayed as 12.34 ppm.

Process setpoint set by the operator through the Setpoint menu. This number is scaled to the range of the displayed process value based on the decimal point and exponent settings of the instrument.

Range = -999 to 9999

Default = 0.000

Timer setpoint set via the Host port or locally.

Range = 0 to 999 minutes

Default = 0

This value is the calculated process value shown as an integer. The decimal point and exponent values are required to determine the actual scaled value.

Range = -999 to 9999.

For example: If the process = oxygen, display decimal point = 2, and exponent = 6, and

PROC = 1234, then the actual value and displayed as 12.34 ppm.

This is the remaining time on the timer as it counts down from Time Setpoint. Zero indicates timer has stopped.

Range = 0 to 999 minutes

Default = 0

READ/WRITE

READ ONLY

READ/WRITE

READ ONLY

READ ONLY

Alarm value is based on process value display decimal point and exponent. Both are required to determine the real alarm value.

READ/WRITE

Range = -999 to 9999.

Default = 0000

Alarm value is based on process value display decimal point and exponent. Both are required to determine the real alarm value.

READ/WRITE

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HEX

BLOCK 0

DEC PARAMETER DESCRIPTION

Range = -999 to 9999.

Default = 0000

BITS 0 – 3

0000 = OFF (DEFAULT)

0001 = DEVIATION BAND

0010 = BAND LOW

0011 = BAND HIGH

0100 = PERCENT OUT LOW

0101 = PERCENT OUT HIGH

0110 = FULL SCALE LOW

0111 = FULL SCALE HIGH

1000 = PROBE IMPEDANCE / VERIFY

1001 = SPARE

1010 = SPARE

1011 = SPARE

1100 = START

1101 = SOAK

1110 = TIMER

1111 = FAULT

BIT 4 ACTION CONTROL

0 = DIRECT

1 = REVERSE

BIT 5 NO LATCH = 0, LATCHED = 1

BIT 6 – 15 SPARE

BITS 0 – 3

0000 = OFF (DEFAULT)

0001 = DEVIATION BAND

0010 = BAND LOW

0011 = BAND HIGH

0100 = PERCENT OUT LOW

0101 = PERCENT OUT HIGH

0110 = FULL SCALE LOW

0111 = FULL SCALE HIGH

1000 = PROBE IMPEDANCE / VERIFY

1001 = SPARE

1010 = SPARE

1011 = SPARE

1100 = START

1101 = SOAK

1110 = TIMER

1111 = FAULT

BIT 4 ACTION CONTROL

0 = DIRECT

1 = REVERSE

Dew Point

READ/WRITE

READ/WRITE

READ/WRITE

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HEX

BLOCK 0

DEC PARAMETER DESCRIPTION

0A

0B

0C

0D

0E

0F

10

Dew Point

10

11

PB

RESET

BIT 5 NO LATCH = 0 LATCHED = 1

BIT 6 – 15 SPARE

Proportional Band – Based on display units

Range = 1 to 9999

Default = 20

Reset – Based on seconds

Range = OFF to 9999

Where 0020 is assumed to be 00.20 seconds

Default = OFF (reset value = 0)

12

13

14

15

16

RATE

CYCTIM

LDLN

HIPO

LOPO

Rate – Based on seconds

Range = OFF to 9999

Where 0020 is assumed to be 00.20 seconds

Default = OFF (rate value = 0)

Cycle Time – Based on seconds

Range = 0.2 to 9999

Where 0002 is assumed to be 0002 seconds

Default = 30

Load Line – Range = -100 to 100

Default = 0

Control Output High Limit

Range = -100 to 100 where HIPO is always greater than LOPO.

Default = 100

Control Output Low Limit

Range = -100 to 100 where LOPO is always less than HIPO.

Default = 0

Type

BITS 0 – 2 = CONTROL PARAMETER

000 = SPARE

001 = Temperature

010 = Millivolt INPUT B

011 = DEWPT

100 = Dewpoint

101 = Oxygen

110 = Redox

111 = Millivolt INPUT A

BIT 3 = NORMAL (0) FREEZE CONTROL

OUTPUT (1)

BITS 4 – 6 = MODE

000 = TIME PROPORTIONING

001 = TIME PROP W/ COMPLEMENT

010 = TIME PROP, DUAL

011 = SPARE

100 = ON/OFF

101 = ON/OFF W/ COMPLEMENT

110 = ON/OFF, DUAL

111 = VALVE POSITIONING W/ FEEDBACK

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

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HEX

BLOCK 0

DEC PARAMETER DESCRIPTION

12

13

14

15

18 CONFIG0

19 CTRLOUT

20 ALRMT1

21 ALRMT2

Dew Point

BIT 7 = DIRECT (0) OR REVERSE (1)

ACTING

BIT 8 = MANUAL (0) OR AUTO (1)

BIT 9 = SETPT LOCAL (0) OR SETPT

REMOTE (1)

BIT 10 = MONITOR (0), CONTROLLER (1)

BITS 11 = SENSOR BREAK OUTPUT 0 (0),

OUTPUT HOLD (1)

BITS 12 – 15 NOT USED

Input Configuration

BITS 0-3 TC Input TYPE

0000 = B (DEFAULT)

0001 = E

0010 = J

0011 = K

0100 = N

0101 = R

0110 = S

0111 = T

1000 = SPARE

1001 = SPARE

1010 = SPARE

1011 = SPARE

1100 = SPARE

1101 = SPARE

1110 = SPARE

1111 = SPARE

BIT 4 = SPARE

BIT 5 0 = NO CJ APPLIED, 1 = CJ APPLIED

BIT 6 0 = °F, 1 = °C

BIT 7 0 = 60HZ FILTER

BIT 8 – 11 Millivolt Input TYPE

0000 = LINEAR (DEFAULT)

All other bit combinations are spare

BITS 12 – 15 are spare

Control Output, unsigned integer

Actual control output where:

1000 = 100.0% and 64536 = -100.0%

ALARM 1 ON/OFF TIMES

RANGE = 0 – 255 SECONDS

DEFAULTS = 0

BIT 0-7 = ON TIME

BIT 8-15 = OFF TIME

ALARM 2 ON/OFF TIMES

RANGE = 0 – 255 SECONDS

DEFAULTS = 0

BIT 0-7 = ON TIME

BIT 8-15 = OFF TIME

READ/WRITE

READ/WRITE

READ ONLY

READ/WRITE

READ/WRITE

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HEX

BLOCK 0

DEC PARAMETER DESCRIPTION

16

17

22 FAULT

23 CJTRM AND

COMP

Dew Point

FAULT BIT MAP

BIT 0 = Temperature Input Open

BIT 1 = MV Input Open

BIT 2 = Range of input is low

BIT 3 = Range of input is high

BIT 4 = Timer End

BIT 5 = Probe Care Fault

BITS 6 – 7 = SPARE

BIT 8 = CPU Fault

BIT 9 = Min Idle counter = 0

BIT 10 = Keyboard failure, stuck key or a key was pressed during power up.

BIT 11 = Flash Erase Failed

BIT 12 = Flash Checksum Failed

BIT 13 = EEPROM Checksum Failed

BIT 14 = Flash/EEPROM Size Fault

BIT 15 = ADC Fault

LOW BYTE – CO / H COMPENSATION

RANGE 0 – 255

DEFAULT = 20 (% CO FOR DEWPT)

DEFAULT = 40 (% H2 FOR DEWPOINT)

HIGH BYTE – COLD JUNCTION TRIM

COLD JUNCTION TRIM (unsigned integer)

RANGE = –128 TO +127 WHERE

1 COUNT = 1 DEG (C or F) and –128 = 65408

READ/WRITE

READ ONLY

READ/WRITE

HEX

18

BLOCK 1

DEC PARAMETER DESCRIPTION

24 ASRC ANALOG OUT SOURCES

LOW BYTE, ANALOG OUTPUT 1

BITS 0 – 3

0000 = N/A

0001 = Temperature

0010 = Linear Input A

0011 = DEWPT value

0100 = Dewpoint value

0101 = Oxygen value

0110 = Redox value

0111 = Output Power

1000 = Control Output 1

1001 = Control Output 2

1010 = Linear Input B

1011 = Programmable*

*For Programmable, write required output value into DACV1, where DACV1 = 0 is minimum output and

DACV1 = 4096 is maximum output.

BITS 4 – 7 SPARE

READ/WRITE

READ/WRITE

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BLOCK 1

DEC PARAMETER DESCRIPTION

19

1A

1B

1C

1D

25 AOUTOF1

26 AOUTRN1

27 AOUTOF2

28 AOUTRN2

29 TEMPFIL

Dew Point

READ/WRITE

HIGH BYTE, ANALOG OUTPUT 2

BITS 8 – 12

0000 = N/A

0001 = Temperature

0010 = Linear Input A

0011 = DEWPT value

0100 = Dewpoint value

0101 = Oxygen value

0110 = Redox value

0111 = Output Power

1000 = Control Output 1

1001 = Control Output 2

1010 = Linear Input B

1011 = Programmable*

*For Reference Number and Programmable , write required output value into DACV2, where

DACV2 = 0 is minimum output and

DACV2 = 4096 is maximum output.

BITS 13 – 15 SPARE

Special case: If Analog Output 1 = CONTROL

OUTPUT 1 and Analog Output 2 = CONTROL

OUTPUT 2 and the Control Mode is dual, then

Analog Output 1 is 4-20ma for 0 to +100% PO and Analog Output 2 is 4-20ma for 0 to -100%

PO.

ANALOG OUTPUT 1 OFFSET

Minimum source value that correlates to minimum Analog Output of 4 mA. The source value is based on the selection in ASRC lower byte

ANALOG OUTPUT 1 RANGE

Maximum source value that correlates to maximum Analog Output of 20 mA. The source value is based on the selection in

ASRC lower byte where

ANALOG OUTPUT 2 OFFSET

Minimum source value that correlates to minimum Analog Output of 4 mA. The source value is based on the selection in ASRC upper byte

ANALOG OUTPUT 2 RANGE

Maximum source value that correlates to maximum Analog Output of 20 mA. The source value is based on the selection in

ASRC upper byte where

Temperature Input Filter in seconds

Range = 0 to 3276. The higher the number

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

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BLOCK 1

DEC PARAMETER DESCRIPTION

Dew Point

READ/WRITE

1E

1F

30

31

MVFIL

CONFIG2 the faster the reading update.

DEFAULT = 1000

Millivolt Input Filter in seconds

Range = 0 to 3276. The higher the number the faster the reading update.

DEFAULT = 1000

SETUP VALUES

BITS 0 - 4 OXYGEN EXPONENT

RANGE = 0 to 31, where 2 = % and 6 = ppm

DEFAULT = 2

BITS 5 - 6 DISPLAY DECIMAL PLACE where:

0 = no decimal point in display

1 = Display XXX.X

2 = Display XX.XX

3 = Display X.XXX

DEFAULT = 0

BITS 8 – 12 REDOX METAL NUMBER

RANGE = 0 – 14

DEFAULT = 0

BITS 13 – 15 SPARE

COLD JUNCTION 20 32 COLDJCT

Where 1 COUNT = 1°F (°C), RANGE = -99 TO

255°F (°C). Note this parameter is an unsigned integer.

21 33 TEMPERATURE

Where temperature is presented in degrees C or F, based on the C/F setting. Note this parameter is an unsigned integer of temperature -2721 = 62815

Range = max / min range of selected thermocouple.

MILLIVOLT

Where this value is scaled in 0.1 mV increments, i.e. 10001 = 1000.1.

Range = 0 to 2000 mV.

READ/WRITE

READ/WRITE

READ ONLY

READ ONLY

READ ONLY

READ/WRITE

SIOSET BITS 0-7

RANGE = 0 – 255

HIGH BYTE – SIO SETUP

BITS 8 – 9 PARITY SETTING

00 = Even Parity, 7 bits, 1 Stop bit

01 = No Parity, 8 bits, 1 Stop bit

10 = Odd Parity, 7 bits, 1 Stop bit

BITS 10 – 11 RESPONSE DELAY

0 = No delay applied to response

1 = 10ms delay applied to response

2 = 20ms delay applied to response

3 = 30ms delay applied to response

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BLOCK 1

DEC PARAMETER DESCRIPTION

24

25

26

27

28

29

2A

2B

2C

2D

Dew Point

READ/WRITE

36 PF

BITS 12 – 14 BAUD SELECT

000 = 76.8K

001 = 38.4K

010 = 19.2K (DEFAULT)

011 = 9600

100 = 4800

101 = 2400

110 = 1200

111 = 600

BIT 15 HOST FORMAT

0 = MMI (PROP)

1 = MODBUS (DEFAULT)

PROCESS FACTOR FOR DEWPT OR

DEWPOINT

READ/WRITE

37

38

DACV1

DACV2

RANGE = 0 to 4095

DEFAULT = 150

ANALOG OUTPUT 1

0 to 4095 is 4 to 20 mA In dual mode 4mA = -

100, 12mA = 0, 20mA = +100

ANALOG OUTPUT 2

0 to 4095 is 4 to 20 ma In dual mode 4mA = -

100, 12mA = 0, 20mA = +100

READ/WRITE

READ/WRITE

39 LOCK AND PLIM LOW BYTE – LOCK LEVEL

BITS 0 – 2

LOCK LEVEL; 0-3 0 is full lock, 3 is wide open

READ/WRITE

BITS 3 – 7 SPARE

HIGH BYTE – PROBE IMPEDANCE LIMIT

0 – 255 KOHMS, DEFAULT VALUE = 20K

40 PIMP READ ONLY

41 PRTM

LAST PROBE IMPEDANCE VALUE (KOHMS

X 10) i.e. 25 = 2.5 KOHMS

LAST PROBE RECOVERY TIME FROM

IMPEDANCE TEST (SECONDS)

RANGE = 0 to 255

Available for Redox, DEWPT, and Dewpoint.

READ ONLY

42 PBOMV

43

44

45

PBOTC

PBORT

PREMT

LAST MILLIVOLTS DURING PROBE BURN

OFF

RANGE = -99 TO 2048 i.e. 1018 = 1018 mV

Available for Redox, DEWPT, and Dewpoint.

LAST TEMPERATURE DURING PROBE

BURNOFF RANGE = 0 to 3000 i.e. 1715 = 1715° (F or C based on CONFIG0

BIT 6)

Available for Redox, DEWPT, and Dewpoint.

LAST PROBE BURNOFF RECOVERY TIME

RANGE = 0 – 255 SECONDS

Available for Redox, DEWPT, and Dewpoint.

REMAINING TIME TO NEXT PROBE TEST

RANGE = 0 – 999

READ ONLY

READ ONLY

READ ONLY

READ ONLY

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BLOCK 1

DEC PARAMETER DESCRIPTION

2E

2F

46 VGAS

47 PMC

Dew Point

Where 999 = 99.9 hours

MEASURED VERIFY GAS VALUE

Value = Actual measured oxygen (0.1%)

Verify function available for Oxygen.

PROBE MAINTENANCE CONTROL WORD

BITS 0 – 1

00 = START FULL MAINTENANCE

01 = START BURNOFF (VERIFY) ONLY

10 = START PROBE IMP ONLY

11 = NONE

BITS 2 – 6 UNDEFINED

BIT 7 = NORMAL (0), CANCEL (1)

BITS 8 – 15 = PROBE MAINTENANCE

SEQUENCE NUMBER

READ/WRITE

READ ONLY

READ/WRITE

HEX

30

31

32

33

34

35

DEC PARAMETER

48 PTINT

49 PTRECT

50 BOTM

51 BOREC

52 VSTD

53 VTOL

BLOCK 2

DESCRIPTION

PROBE TEST INTERVAL SETTING (HRS)

Operator input for interval setting

RANGE = 0 – 999

Where 999 = 99.9 hours

DEFAULT = 0 (Disable Probe test)

PROBE TEST RECOVERY TIME SETTING

(SECONDS)

RANGE = 0 to 999

DEFAULT = 30

BURN OFF TIME SETTING (SECONDS)

RANGE = 0 to 999

DEFAULT = 30

Burnoff function available for Redox, DEWPT, and Dewpoint.

BURN OFF RECOVERY TIME SETTING

(SECONDS)

RANGE = 0 to 999

DEFAULT = 30

Burnoff function available for Redox, DEWPT, and Dewpoint.

VERIFY TEST GAS STANDARD

This is the test standard value used to verify the probe.

RANGE = 0 to 999

Where the value 999 = 99.9% oxygen

DEFAULT = 30 (3.0%)

Verify function available for Oxygen.

VERIFY TEST TOLERANCE SETTING

This setting establishes the limit as VSTD

±

VTOL when comparing to the measured value

VGAS

Range = 0 to 999

Where 0005 = 00.5%

DEFAULT = 0005

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

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37

38

39

3A

3B

3C

3D

3E

3F

40

43

45

Dew Point

DEC PARAMETER

BLOCK 2

DESCRIPTION

55

56

57

TDEL1

TDEL2

TMIN

58 TC_ZERO

59 TC_SPAN

60 MV_ZERO

Verify function available for Oxygen.

VERIFICATION SAMPLE AVERAGING

SETTING (SECONDS)

RANGE = 0 to 999

DEFAULT = 2

Verify function available for Oxygen.

VERIFY DELAY 1 SETTING (SECONDS)

RANGE = 0 to 999

DEFAULT = 30

Verify function available for Oxygen.

VERIFY DELAY 2 SETTING (SECONDS)

RANGE = 0 to 999

DEFAULT = 30

Verify function available for Oxygen.

MINIMUM TEMPERATURE FOR PROBE

CARE TEST

This setting establishes the lowest process temperature allowed for a probe test to proceed.

RANGE = 500°F to 2000°F (260°C to 1090°C)

DEFAULT = 1400°F (760°C)

TC ZERO CALIBRATION NUMBER

TC SPAN CALIBRATION NUMBER

MV ZERO CALIBRATION NUMBER

61 MV_SPAN MV SPAN CALIBRATION NUMBER

62 DAC_OFFSET_1 DAC 1 OFFSET CALIBRATION

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

READ/WRITE

63 DAC_SPAN_1 DAC 1 SPAN CALIBRATION READ/WRITE

64 DAC_OFFSET_2 DAC2 OFFSET CALIBRATION READ/WRITE

DAC2 CALIBRATION READ/WRITE

READ/WRITE

67

69

ANUM

BNUM

OFFSET, Y INTERCEPT LINEAR

SCALING FOR INPUT A

LINEAR SPAN VALUE FOR INPUT A

OFFSET, Y INTERCEPT LINEAR

SCALING FOR INPUT B

LINEAR SPAN VALUE FOR INPUT B

READ/WRITE

READ/WRITE

READ/WRITE

TIME

AND EVNT

LOW BYTE – INPUT EVENT

CONFIGURATION

Bits 0 – 3

0000 = None

0001 = Auto Mode Selected

0010 = Remote Setpoint Selected

0011 = Acknowledge alarms

0100 = Timer Hold

0101 = Timer End

0110 = Timer Start

0111 = Start probe test

1000 = Process hold

Bits 4 – 7 not used.

HIGH BYTE - TIMER CONTROL

READ/WRITE

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Dew Point

BLOCK 2

DESCRIPTION

BIT 0 – SPARE

BIT 1 – Timer stop(0), Timer start(1)

BIT 2 – Timer running(1)

BIT 3 – Timer End Active(1)

BIT 4 – Timer Hold Active(1)

BIT 5 – 6 SPARE

BIT 7 = Timer Disabled (0), Timer Enabled

(1)

READ/WRITE

94

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Key Features

  • Single loop process controller
  • Two channel 24 bit Sigma-Delta ADC
  • Two 4-20mA outputs
  • RS 485 serial communication
  • Two Form A alarm contacts
  • Internal relay for sensor burnoff
  • Internal relay for sensor impedance testing

Frequently Answers and Questions

What are the required rear clearance for the VersaPro?
7” to allow for wiring
What is the power supply required for the VersaPro?
120/240 VAC 50/60 Hz
What type of sensors can be used with the VersaPro?
Zirconia carbon sensors and standard thermocouple types
What are the available process functions for the VersaPro?
Dew Point, Linear Input A, Linear Input B

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