Critical Environment Technologies SCD SERIES SELF-CONTAINED PROGRAMMABLE GAS DETECTION SYSTEMS gas detector Installation / operation manual

Below you will find brief information for gas detector SCD SERIES SELF-CONTAINED PROGRAMMABLE GAS DETECTION SYSTEMS. The SCD series gas detectors offer various features, including user-adjustable time delays for low and high gas alarms, a 4-20 mA output signal for integration with other systems, and a choice of remote sensor types for different applications. This manual guides you through the installation, operation, and maintenance of your new gas detector.

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Critical EnvironmentTechnologies

SCD SERIES SELF-CONTAINED

PROGRAMMABLE GAS DETECTION SYSTEMS

INSTALLATION / OPERATION MANUAL

REV: F DEC-15-2001

Unit 145, 7391 Vantage Way Delta, BC V4G 1M3

Canada Ph: 604-940-8741 Fx: 604-940-8745 www.critical-environment.com

IMPORTANT NOTICES

READ AND UNDERSTAND THIS OPERATION MANUAL PRIOR TO USING THIS

INSTRUMENT.

THIS INSTRUMENT SHOULD BE INSPECTED AND CALIBRATED AT

REGULAR INTERVALS BY QUALIFIED AND TRAINED PERSONNEL. FOR MORE

INFORMATION REFER TO THE “SYSTEM MAINTENANCE” AND “CALIBRATION

PROCEDURE” SECTIONS OF THIS MANUAL.

THIS INSTRUMENT HAS NOT BEEN DESIGNED TO BE INTRINSICALLY SAFE.

FOR YOUR SAFETY, DO NOT USE IT IN CLASSIFIED HAZARDOUS AREAS

(EXPLOSION-RATED ENVIRONMENTS).

PURCHASE DATE:

_________________________________________________

PURCHASED FROM:

_______________________________________________

WARNINGS

•

DISCONNECT POWER BEFORE SERVICING

•

CAUTION: MORE THAN ONE LIVE CIRCUIT

•

SUPPLY: NOMINAL 24 VDC OR 24 VAC (CLASS II TRANSFORMER).

OPTIONAL: 120VAC OR 240 VAC, 50 OR 60 HZ.

•

CERTIFIED FOR ELECTRICAL SHOCK AND ELECTRICAL FIRE HAZARD

ONLY

WARRANTY POLICY

CRITICAL ENVIRONMENT TECHNOLOGIES CANADA INC. WARRANTS THIS

INSTRUMENT TO BE FREE FROM DEFECTS IN MATERIALS AND

WORKMANSHIP FOR A PERIOD OF TWO (2) YEARS FROM THE DATE OF

PURCHASE. INDIVIDUAL SENSOR ELEMENTS HAVE DIFFERENT

WARRANTIES. THE WARRANTY STATUS MAY BE EFFECTED IF THE

INSTRUMENT HAS NOT BEEN MAINTAINED AND CALIBRATED AS PER THE

INSTRUCTIONS INDICATED IN THIS MANUAL OR HAS BEEN ABUSED OR

DAMAGED IN ANY WAY. THIS INSTRUMENT IS ONLY TO BE USED FOR

PURPOSES STATED HEREIN.

INDEX

SECTION DESCRIPTION PAGE

1.0 General ................................................................................................7

2.0 Controller Specifications ......................................................................7-8

2.1 Sensor Specifications ..........................................................................8-11

2.2 Sensor Mounting Heights ....................................................................11

3.0 System Enclosure Drawing (Low Voltage) ..........................................12

3.1 System Interior Layout Drawing (Low Voltage) ...................................13

3.2 System Enclosure Drawing (Low Voltage) c/w Strobe Light Option ....14

3.3 System Enclosure Drawing (Line Voltage) ..........................................15

3.4 System Interior Layout Drawing (Line Voltage) ...................................16

3.5 Dual Integral CO/NO2 System Enclosure Drawing .............................17

3.6 Dual Integral CO/NO2 System Interior Layout Drawing ......................18

3.7 System Controller with Strobe Light & Output Signal Options .............19

3.8 System (Line Voltage) with Strobe Light Option ..................................20

4.0 Circuit Board Key Component Identification ........................................21

5.0 Sensor Hook-Up Drawing, Single Remote Digital Sensor ...................22

5.1 Sensor Hook-Up Drawing, Dual Remote Digital Sensors ....................23

6.0 Remote Sensor Enclosure Photo General Purpose ............................24

6.1 Remote Sensor Enclosure photo Water/Dust Tight .............................24

6.2 Remote Sensor Wiring .........................................................................24

6.3 Remote Sensor Connections Wiring Photo .........................................25

6.4 Output Signal Board 4-20 mA ..............................................................26

7.0 System Installation ...............................................................................26-27

7.1 Remote Sensor Head Installation ........................................................27

INDEX, CONT’D.....

SECTION DESCRIPTION PAGE

8.0 System Operation ................................................................................27-29

8.1 DIP Switch Labeling .............................................................................29

8.2 DIP Switch Settings for Sensor Configurations ...................................29

8.3 Connections Circuit Board for Remote Horn Option ............................30

9.0 Push-Button Menu Codes ....................................................................31

10.0 Menu Function Items ...........................................................................31-35

11.0 System Maintenance ...........................................................................35

11.1 Calibration Procedure ..........................................................................35-36

11.2 Calibration Set-Up Drawing .................................................................37

12.0 Trouble Shooting .................................................................................38

13.0 Replacement / Spare Parts List ...........................................................38

1.0 GENERAL

The SCD series systems are cost effective, programmable, microprocessor based, selfcontained gas detectors for non-hazardous (non-explosion rated) commercial and light industrial applications. They are available in two basic configurations. One sensor models and two sensor models. The sensors can be configured as one integral or one remote, or one integral and one remote or two remote.

A basic system provides one common set of LED indicating lights for “Power”, “Fail”, “Low

(Warning) Gas Alarm”, ‘High Gas Alarm”, an integral audible alarm with silence push-button, field settable time delays and two alarm relays. Optional accessories include an LED digital display, 4-20 mA output signal, strobe light, and louder audible alarms. Each system comes with two extra LEDs that represent channel numbers. In a two channel (sensor) system, the

LED indicating lights and digital display (if this option has been chosen) are displayed for approximately 2 seconds for each channel and the channel LED’s indicate which channel is being displayed (1 or 2).

A good selection of electrochemical and MOS (Metal Oxide Semi-conductor) solid-state gas sensors are available for use within the SCD series systems.

2.0 CONTROLLER SPECIFICATIONS

Physical: Low Voltage Powered Systems:

a) Dimensions: 7.313” Wide X 8” High X 3.313” Deep

(186 mm Wide X 203 mm High X 84 mm Deep)

b) Weight: 1.2 pounds (.54 kg).

Line Voltage Powered Systems:

a) Dimensions: 8.75” Wide X 11.5” High X 3.55” Deep

(222 mm Wide X 292 mm High X 90 mm Deep)

b) Weight: 3.49 pounds (1.585 kg)

Materials: a) System enclosures: Very rugged PVC (drip proof) with hinged,

secured door and Lexan door label

b) Remote sensor enclosure:

1) Standard: General Purpose PVC with hinged, secured door and

Lexan door label

2) Optional: Water/dust tight, corrosion resistant

Polycarbonate with hinged, secured door and Lexan door label

Indicators: a) Visual: Common set of LED indicating lights for “Power”, “Fail”, “Low

(Warning) Gas Alarm”, “High Gas Alarm”.

b) Audible: Integral piezo audible alarm c/w silence push-button. Rated

80 dB @ 10’

c) Option: 4-digit, LED digital display for “PPM”, “%LEL” or “% Volume”

Environment: a) Temperature: 0 deg. C. to +40 deg. C. (32 deg. F. to 104 deg. F.)

b) Humidity: 0 to 95% non-condensing

Power: Standard: 24 VDC or 24 VAC nominal, (15 to 40 VDC).

Approximately 175 mA. (not including optional accessories).

Optional: 120 or 240 VAC, 50 or 60 Hz, 20 VA.

Relays: Two S.P.D.T. dry contact relays, rated 5 amps @ 240 VAC.

NOTE: System is configured such that all relays are “FAIL-SAFE” (always

energized in non-alarm state). This can be changed through the 3-button keypad.

2.0 CONTROLLER SPECIFICATIONS, CONT’D.....

Circuit: Programmable microprocessor with user settable time delays.

Accessible with potentiometers & DIP switches on circuit board.

Time Delays: a) Delay “ON” (on make) : One adjustable potentiometer in 0.1 minute (6

second) increments for each relay. Just “dial in” the desired time delay

from 0.0 to 12.7 minutes.

b) Delay “OFF” (on break): Also known as “minimum run time”. DIP

switch selectable. Positive “ON / OFF” switch for each relay. ON = 10

minutes

Options: a) LED digital display

b) 4-20 mA output signal (programmable)

c) Slightly louder sonalert audible alarm (90 dB)

d) Top mounted strobe light (3” diameter)

e) Very loud (103 dB) horn

Distance: Maximum 500’ between controller and remote sensor(s)

Sensors: a) Integral:

1. Carbon Monoxide (CO): HVAC electrochemical

2. Carbon Monoxide (CO): Industrial electrochemical

3. Nitrogen Dioxide (NO2): electrochemical

4. Chlorine (Cl2): electrochemical

5. Ammonia (NH3): electrochemical

6. Nitric Oxide (NO): electrochemical

7. Hydrogen Sulphide (H2S): electrochemical

8. Sulphur Dioxide (SO2): electrochemical

9. Hydrogen (H2): electrochemical (ppm ranges)

10. Ethylene Oxide (ETO): electrochemical

11. Oxygen (O2): electrochemical

12. Ozone (O3): electrochemical

b) Remote:

1. All of the above electrochemical sensors

2. Combustible gases & vapours: solid-state or catalytic

3. Ammonia (NH3): solid-state

4. Refrigerants (Freons): solid-state

2.1 SENSOR SPECIFICATIONS

Carbon Monoxide (CO): HVAC electrochemical

* Range: 0 - 200 ppm (other ranges available)

* Response Time: <30 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 2% of signal

* Life Span: 5 years in air (under normal conditions)

Carbon Monoxide (CO): Industrial electrochemical

* Range: 0 - 250 ppm (other ranges available)

* Response Time: <30 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal / month

* Repeatability: 2% of signal

* Life Span: 2 to 3 years in air (under normal conditions)

2.1 SENSOR SPECIFICATIONS, CONT’D…..

Nitrogen Dioxide (NO2):

* Range: 0 - 5 ppm (other ranges available)

* Response Time: <35 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal / month

* Repeatability: 2% of signal

* Life Span: 2 to 3 years in air (under normal conditions)

Chlorine (Cl2):

* Range: 0 - 5 ppm (other ranges available)

* Response Time: <60 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 2% of signal

* Life Span: 2 years in air (under normal conditions)

Ammonia (NH3):

* Range: 0 - 100 ppm (other ranges available)

* Response Time: <60 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +40 deg. C.

* Long Term Drift: <5% signal loss / 6 months

* Repeatability: better than 10% of signal

* Life Span: 1-2 years in air (under normal conditions)

Nitric Oxide (NO):

* Range: 0 - 100 ppm (other ranges available)

* Response Time: <10 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal / month

* Repeatability: 2% of signal

* Life Span: 2 to 3 years in air (under normal conditions)

Hydrogen Sulphide (H2S):

* Range: 0 - 50 ppm (other ranges available)

* Response Time: <30 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 2% of signal

* Life Span: 2 to 3 years in air (under normal conditions)

Sulphur Dioxide (SO2):

* Range: 0 - 10 ppm (other ranges available)

* Response Time: <15 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss/ month

* Repeatability: 2% of signal

* Life Span: 2 to 3 years in air (under normal conditions)

Hydrogen (H2):

* Range: 0 - 1000 ppm (other ranges available)

* Response Time: <30 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 2% of signal

* Life Span: 2 years in air (under normal conditions)

2.1 SENSOR SPECIFICATIONS, CONT’D.....

Ethylene Oxide (ETO):

* Range: 0 - 20 ppm (other ranges available)

* Response Time: <90 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 2% of signal

* Life Span: 2 years in air (under normal conditions)

Oxygen (O2):

* Range: 0 - 25% Volume

* Response Time: <15 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <2% signal loss / month

* Repeatability: 0.2% Vol. or better

* Life Span: 2 years in air (under normal conditions)

Ozone (O3):

* Range: 0 - 1.0 ppm

* Response Time: <60 seconds to 90% of signal response

* Operating Temp. Range: -10 deg. C. to +40 deg. C.

* Long Term Drift: <5% (per 6 months)

* Resolution: 0.02 ppm

* Life Span: 1 1/2 years in air (under normal conditions)

Combustibles: Solid-state, remote only, model: RDS-SCB

* Range: 0 - 50 % LEL

* Response Time: <30 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: <5% signal loss / month

* Repeatability: +/- 10% of signal

* Life Span: 5 years plus in air (under normal conditions

Ammonia: Solid-state, remote only, model: RDS-SAM

* Range: 0 - 1000 ppm

* Response Time: < 120 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: < 5% signal loss / month at ambient temperatures

* Repeatability: +/- 10% of signal below 100 ppm

* Life Span: 3 years plus in air

Refrigerants: Solid-state, remote only, model: RDS-SR0 RDS-SR1, RDS-SR2

* Range: 0 - 1000 ppm

* Response Time: < 120 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: < 5% signal loss / month at ambient temperatures

* Repeatability: +/- 10% of signal above 50 ppm

* Life Span: 5 years plus in air

* Typical freon examples: R12, R502

2.1 SENSOR SPECIFICATIONS, CONT’D.....

Refrigerants: Solid-state, remote only, model: RDS-SR1

* Range: 0 - 1000 ppm

* Response Time: < 120 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: < 5% signal loss / month at ambient temperatures

* Repeatability: +/- 10% of signal above 50 ppm

* Life Span: 5 years plus in air

* Typical freon examples: R22, R401A, R402A

Refrigerants: Solid-state, remote only, model: RDS-SR1

* Range: 0 - 1000 ppm

* Response Time: < 120 seconds to 90% of signal response

* Operating Temp. Range: -20 deg. C. to +50 deg. C.

* Long Term Drift: < 5% signal loss / month at ambient temperatures

* Repeatability: +/- 10% of signal above 50 ppm

* Life Span: 5 years plus in air

* Typical freon examples: R11, R123, R134A, R507

2.2 SENSOR MOUNTING HEIGHTS

Carbon Monoxide: 4’ to 6’ from the floor (breathing air zone)

Nitrogen Dioxide: 4’ to 6’ from the floor (breathing air zone)

Chlorine: 6” from the floor

Ammonia: On or near the ceiling

Nitric Oxide: 6” from the floor

Hydrogen Sulphide: 6” from the floor

Sulphur Dioxide: 6” from the floor

Hydrogen On or near the ceiling

Ethylene Oxide: 6” from the floor

Oxygen: 4’ to 6’ from the floor

Ozone: 1’ from thr floor (application dependent)

Combustibles: Propane: 6” from the floor

Methane: On or near the ceiling

Hexane: 6” from the floor

Refrigerants: 6” from the floor

3.0 SYSTEM (LOW VOLTAGE POWERED) ENCLOSURE DRAWING

NOTE-1: The above drawing depicts a low voltage powered controller with the

“Optional” LED digital display

3.1 SYSTEM (LOW VOLTAGE POWERED) INTERIOR LAYOUT DRAWING

3.2 SYSTEM (LOW VOLTAGE POWERED) STROBE LIGHT OPTION DRAWING

NOTE-1: The above drawing depicts a low voltage powered controller with the

“Optional” LED digital display and “Optional” top mounted strobe light. The strobe light is 3” diameter and available only with a red lens. It is activated upon low level

alarm condition.

3.3 SYSTEM (LINE VOLTAGE POWERED) ENCLOSURE DRAWING

NOTE-1: The above drawing depicts a line voltage powered controller with the

“Optional” LED digital display

3.4 SYSTEM (LINE VOLTAGE POWERED) INTERIOR LAYOUT DRAWING

3.5 DUAL INTEGRAL CO/NO2 SYSTEM ENCLOSURE DRAWING

NOTE-1: The above drawing depicts a line voltage powered controller with an integral, electrochemical CO sensor and integral electrochemical NO2 sensor / transmitter.

This drawing also shows the “Optional” LED digital display.

3.6 DUAL INTEGRAL CO/NO2 SYSTEM INTERIOR LAYOUT DRAWING

3.7 SYSTEM (LINE VOLTAGE POWERED) 4-20 mA & AUDIBLE OPTION DRAWING

NOTE-1: The above drawing shows a circuit board, located in the base of the enclosure.

This circuit board provides two, linear, scalable 4-20 mA signal outputs. One for each channel.

NOTE-2: The 4-20 mA output signal option is also available with the low voltage powered controller.

3.8 SYSTEM (LINE VOLTAGE POWERED) STROBE LIGHT OPTION DRAWING

NOTE-1: The above drawing depicts a line voltage powered controller with the

“Optional” LED digital display and “Optional” top mounted strobe light. The strobe light is 3” diameter and available only with a red lens. It is activated upon low level

alarm condition.

4.0 CIRCUIT BOARD KEY COMPONENT IDENTIFICATION

DIP INTERNAL PROGRAMMING AUTOMATIC

SWITCHES SERVICE PUSH-BUTTONS RESETTING

DISPLAY SYSTEM FUSE

SYSTEM TIME DELAY ELECTROCHEMICAL RELAYS

SOFTWARE “ON” POTS. SENSOR SOCKETS

5.0 SENSOR HOOK-UP DRAWING, SINGLE REMOTE DIGITAL SENSOR

INTERNAL USE

NOT USED

LOW VOLTAGE POWERED SYSTEM:

INSTALLER SUPPLIED 24V AC OR DC

(NOMINAL) WIRING.

LINE VOLTAGE POWERED SYSTEM:

FACTORY WIRES FROM SYSTEM

INSTALLER SUPPLIED LOW-VOLTAGE WIRING

FOR REMOTE SENSOR. ONLY USE THIS

TERMINAL IF THERE IS NO INTEGRAL SENSOR

WIRING FROM DEVICES CONTROLLED BY HIGH

ALARM RELAY (EG. REMOTE ALARMS, ETC.)

WIRING FROM DEVICES CONTROLLED BY LOW ALARM

RELAY (EG. EXHAUST FANS, MAKE UP AIR FANS, ETC.)

NOTE-1: System Relays are dry contacts and designed to operate fan starters or coils to control equipment that draws no more than 5 amps start/up and/or operational current. System default is “fail-safe” (relays coils normally energized in non-gas-alarm state). Control wiring should be connected to “N/C” and “COM” terminals. If relay coils are to be set to “non fail-safe”, use “N/O” and “COM” terminals. DO NOT USE SOLID-CORE WIRE ON TERMI-

NALS.

NOTE-2: No power is provided from system relay terminals.

5.1 SENSOR HOOK-UP DRAWING, DUAL REMOTE, DIGITAL SENSORS

INTERNAL USE

LOW VOLTAGE POWERED SYSTEM:

INSTALLER SUPPLIED 24V AC OR DC

(NOMINAL) WIRING.

LINE VOLTAGE POWERED SYSTEM:

FACTORY WIRES FROM SYSTEM

INSTALLER SUPPLIED LOW-VOLTAGE WIRING

FOR CHANNEL-2 REMOTE SENSOR.

INSTALLER SUPPLIED LOW-VOLTAGE WIRING FOR

CHANNEL-1 REMOTE SENSOR. ONLY USE THIS TERMI-

NAL IF THERE IS NO INTEGRAL SENSOR INSTALLED

WIRING FROM DEVICES CONTROLLED BY HIGH

ALARM RELAY (EG. REMOTE ALARMS, ETC.)

WIRING FROM DEVICES CONTROLLED BY LOW ALARM RE-

LAY (EG. EXHAUST FANS, MAKE UP AIR FANS, ETC.)

NOTE-1: System relays are dry contacts and designed to operate fan starters or coils to control equipment that draws no more than 5 amps start/up and/or operational current. System default is “fail-safe” (relays coils normally energized in non-gas-alarm state). Control wiring should be connected to “N/C” and “COM” terminals. if relay coils are to be set to “non failsafe”, use “N/O” and “COM” terminals. DO NOT USE SOLID-CORE WIRE ON TERMINALS.

NOTE-2: No power is provided from system relay terminals.

6.0 REMOTE SENSOR ENCLOSURE PHOTO, GENERAL PURPOSE

6.1 REMOTE SENSOR ENCLOSURE PHOTO, WATER/DUST TIGHT

6.2 REMOTE SENSOR WIRING

Three (3) conductor, 18 to 20 gauge low voltage shielded wire is required between the control panel and each remote sensor. Shielding is not required if conduit is utilized. Do not run unshielded wires in same conduit as line voltage wires.

6.3 REMOTE SENSOR CONNECTION WIRING PHOTOS

< POS

< NEG

< SIG

ELECTROCHEMICAL SENSOR

Note: Inside of general purpose pvc transmitter enclosures doors shown.

< POS

< NEG

< SIG

SOLID-STATE SENSOR

6.4 OUTPUT SIGNAL BOARD 4-20 mA

4-20 mA loop indicator LEDs.

They illuminate if the signal is interrupted or wiring is not connected properly.

7.0 SYSTEM INSTALLATION

Loosen screw securing the hinged door. There are four only 3/16” diameter corner mounting holes located inside the system enclosure base. Secure the system to any flat surface. a) Low voltage power: Drill out PVC conduit entry hole plug located at bottom center of system enclosure base and attach conduit to this location. Pull two 16 - 18 gauge wires from power source to the terminal strips labeled 24 VAC or VDC (System Power Hook-up). b) Line voltage power: Drill out one or more of the PVC conduit entry hole plugs located at bottom center or right side of system enclosure base and attach conduit to one or two of these locations. Pull three wires suitable for line voltage from power source to the terminal strips and stud labeled “Line”, “Neutral” and “Ground”, in the base of the enclosure. c) Power to remote sensors: The voltage supplied by the controller to remote sensors should measure approximately 8.5 to 9.0 VDC. Wiring should be 3-conductor, 16 to 20 gauge shielded. d) Relay control wiring: DO NOT USE SOLID-CORE WIRE FOR CONNECTION TO RELAY

TERMINAL STRIPS. Relay control wiring should be connected to “N/C” and “COM” if the system relays are normally energized (default). If system relays have been changed to not normally energized, use “N/O” and “COM”. (reference the specifications to ensure that relay load capacity is not exceeded).

Solid-core wire is unforgiving and if used for relay control connections or any other terminal strip connections on the SCD mother board, can result, over time, in the terminal strips pulling away from the circuit board. THIS TYPE OF DAMAGE IS NOT COVERED UNDER

WARRANTY. e) 4-20 mA output wiring: This option provides two programmable, linear 4-20 mA output signals, one for each senor. Wiring should be shielded 2-conductor 18 to 22 gauge.

7.0 SYSTEM INSTALLATION, CONT’D…..

f) Top Mounted Strobe Light Option: No wiring is required for this option. It comes preinstalled and wired. g) Remote Horn Option: The installer should provide 16 to 18 gauge wiring from a line voltage (120 VAC) source. One wire should run directly to the remote mounted horn and the second wire should run to the horn relay terminal strip “N/C” and from the “COM” terminal strip back to the horn. The horn relay terminal strip inside our enclosure controls the remote horn. Reference photo on page 30.

7.1 REMOTE SENSOR HEAD INSTALLATION

If a remote sensor is supplied (for lighter-than-air or heavier-than-air gases and vapours), the remote PVC or optional polycarbonate sensor enclosure can be flush mounted against any flat surface.

General Purpose Enclosure (pvc): Four only 3/16” diameter mounting holes can be located inside the enclosure base.

Water/Dust Tight, Corrosion Resistant (polycarbonate): Four only 3/16” diameter holes can be located on the inside edge of the enclosure base. They are accessed through the holes for the door securing screws.

Conduit and/or wiring can be introduced to the pvc enclosure through any of the five provided entry ports (top, bottom, back and right side). Only one conduit entry port is provided on the top edge of the polycarbonate enclosure. Note: IF THIS ENCLOSURE IS TO BE UTILIZED

IN A DAMP, VERY WET OR CORROSIVE ENVIRONMENT, BE SURE TO USE THE

APPROPRIATE LIQUID TIIGHT CONDUIT CONNECTOR.

8.0 SYSTEM OPERATION

Power Up: Upon application of power, the front door LED light indicators and the digital display (if this option has been chosen) will illuminate. The outer digital display on the front door will indicate “SCd-”. The inner service digital display will indicate the software version in four digits.

The system immediately goes into a 2 minute warm-up indicated by reducing digits on the inside digital display starting at “120” representing 120 seconds. During this warm-up period, the audible alarm is disabled, however, relays are in a de-energized state. This means that anything controlled by the system relays and the strobe light option (if selected) will be operational until after the count down warm up. After warm up, only the green power

LED illuminates indicating normal operation and the alarm relays are energized indicating normal “fail-safe” status. The energized state of the relays can be confirmed visually by the illuminated amber LED located beside each relay. At this point, the outer digital display (if this option has been selected) will display the actual gas values.

Sensor Fail: In the event of a defective or missing sensor module, the controller will display

“SEnS” on the inner display, the “Fail” LED will illuminate and the audible alarm will be activated. Normal system operation will not resume until the fault condition has been rectified. There is a 15 second delay before the system activates fail (fault) condition alarms.

8.0 SYSTEM OPERATION, CONT’D…..

Gas Alarm: In the event of a gas build up beyond the preset low alarm trip point, the “Low” alarm level LED (amber) illuminates and the “Low” alarm relay de-energizes activating anything controlled by it. If a time delay “ON” has been programmed, then the low alarm relay will not de-energize until the delay has timed out. Once the relay has de-energized, it will re-energize once the gas alarm condition has stabilized, unless a time delay

“OFF” (minimum run time) has been programmed.

If the gas levels continue to rise beyond the preset high alarm trip point, the “High” alarm level LED (red) illuminates, the “High” alarm relay de-energizes activating anything controlled by it and the audible alarm is activated. Again, any programmed time delays “ON” or “OFF” affect the de-energizing and re-energizing of the relay. The audible alarm can be silenced by

depressing the red silence push-button located on the right upper side of the system enclosure door.

System Fail: A system fail condition is indicated by the Fail LED illuminating, the audible alarm activating and both alarm relays being de-energized and anything controlled by them running continuously until the fail condition is corrected. There is a 15 second delay before a

fail condition is activated. A fail condition could be characterized by: a) a burned out sensor element (solid-state), b) a sensor drifting lower than the preset fail level (under flow), c) a damaged circuit board or circuit board component, or d) removal of an integral or remote sensor board. At this point the channel scanning rate increases to 1 second intervals.

Signal Output: If the 4-20 mA output signal option has been selected, a small circuit board is located in the upper section of the enclosure base. This circuit board has one three-position terminal strip at one end for installer wiring. Two red LED light indicators are located on either side of the terminal strip. These are “open loop” indicators. If the 4-20 mA wiring loop is not connected correctly or if one or both of the sensors drifts into the negative and the signal drops below the underflow setting, one or both of the LEDs illuminate and one or both of the output signals drop to “0”. These signal outputs are programmable. The user can set the lower and upper ranges to be represented by 4 mA and 20 mA. The upper signal maximum is 20.0 mA. This makes it compatible with BAC systems that indicate a fail condition at signals above 20 mA.

In the event of an alarm condition with a two sensor configuration, the system stops scrolling between channels and stays on the channel in alarm. However, the 4-20 mA signal output for both channels continues, uninterrupted.

Time Delays: a) Time Delays on “Make”: To achieve a time delay “ON” for the low alarm relay simply adjust potentiometer “RV1” to the desired delay. The inner display will immediately display the value in 0.1 minute (6 second) segments as the user dials in the desired time. Adjust potentiometer “RV2” for any desired time delays “ON” for the high alarm relay. The time delay potentiometers can be located at the bottom left side of the circuit board. b) Time Delays on “Break”: To achieve a time delay on “break” (minimum run time) for the low alarm, set the first switch labeled “RELAY 1” of the DIP switch pack, to the right. (on position). To achieve a time delay on “break” for the high alarm, set the second switch labeled

“RELAY 2” of the DIP pack, to the right. The DIP switch pack can be located on the upper left side of the circuit board. The minimum run time is fixed at 10 minutes for each alarm level.

Refer to the circuit board photo on page 21.

Sensors: The third and fourth switches labeled “CH-2” and “INTEGRAL” are used to select one integral, or one remote, or one integral and one remote or two remote sensor(s). See the diagrams for appropriate DIP switch settings on the next page. Note: Every system is shipped with the DIP switches preset to default settings unless we are advised differently.

8.0 SYSTEM OPERATION, CONT’D…..

Visual Option: If the top mounted strobe light option has been selected, there is an additional small relay circuit board located in the base of the enclosure. The strobe light comes preinstalled and pre-wired from the factory. It is operated with the low level alarm.

Audible Options: a) If the slightly louder sonalert 90 dB option has been selected, it comes pre-installed and pre-wired. This audible alarm is activated with the high alarm level and can be silenced by depressing the red silence push-button located on the upper right outer side of the enclosure door. This option is only supplied in the larger enclosure size.

b) If the remote horn 103 dB option has been selected, it comes separate from the enclosure and must be mounted by the installer. It is controlled by a small relay board located in the base of our enclosure. This audible alarm is activated with the high alarm level and cannot be silenced manually. Refer to section 8.3 for connection information.

NOTE: ALL USER PROGRAMMABLE FUNCTIONS AND OPTIONS CAN BE ACCESSED

AND CHANGED LIVE OR “ON THE FLY”. THE SYSTEM DOES NOT HAVE TO BE POW-

ERED DOWN AFTER MAKING PROGRAMMING OR DIP SWITCH CHANGES.

8.1 DIP SWITCH LABELLING

8.2 DIP SWITCH SETTINGS FOR SENSOR CONFIGURATIONS

8.3 CONNECTION CIRCUIT BOARD FOR REMOTE HORN OPTION

REMOTE MOUNT

HORN: 120 VAC

POWERED

INSTALLER SUPPLIED

WIRING & POWER

SOURCE

120 VAC

POWER

SOURCE

Note: This relay circuit board comes pre-installed in the base of the enclosure. This board is also utilized, internally wired, when the top mounted strobe light or horn option is selected.

9.0 PUSH-BUTTON MENU CODES

FUNCTON

Span Gas Value

Set Null (manual)

Set Span (manual)

Auto Cal

Sensor Defaults

Sensor Type

Decimal Set

Over Flow Threshold

Under Flow Threshold

Power-Up Warm up

Set Low Alarm

Set High Alarm

Relay State

4-20 mA Lower Range

4-20 mA Upper Range

Value Display Inside

Toggle Relays

SCD Defaults

CHANNEL-1

1132

1133

1233

1131

1123

1231

1122

1311

1312

3311

1211

1213

3312

1321

1322

3331

3132

3123

CHANNEL-2

2132

2133

2233

2131

2123

2231

2122

2311

2312

3311

2211

2213

3312

2321

2322

3331

3132

3123

10.0 MENU FUNCTION ITEMS

a) SPAN GAS VALUE: “1132” AND “2132”

These codes allow the user to identify the concentration of span gas being used to calibrate the sensor(s). Enter the 4-digit numeric code “1132” for channel-1 or “2132” for channel-2.

The interior display will display a value. The number displayed is the concentration of gas last used to calibrate each sensor. To change the value, depress push-button “1” to decrement or push-button “3” to increment. When the desired concentration is displayed, depress push-button “2” to accept and the display will indicate “donE”.

10.0 MENU FUNCTION ITEMS, CONT’D..... b) SET NULL (MANUAL): “1133” AND “2133”

This function allows the user to perform a manual “null” (zero) adjustment of each sensor, independent from the “Auto-Cal” procedure. Note: Prior to performing the “null” function, ensure the sensor is in relatively gas free environment. Flow zero emissions air over sensor for at least 2 minutes. Enter “1133” and the internal service display will indicate “CH-1”. Next depress push-button “2”. The display will indicate “null” as it performs a “null” adjustment for channel-1 sensor. If the system in question has two sensors, repeat the procedure for channel-2 sensor by entering “2133”. Note: For user safety, if a background gas concentration of “5” or higher exists, the system will not allow the null function to be performed and the inner display will indicate “GAS”. c) SET SPAN (MANUAL): “1233” AND “2233”

This function allows the user to perform a manual “span” adjustment of each sensor, independent from the “Auto-Cal” procedure. Note: prior to performing the “span” function, ensure that the concentration of span gas has been entered and each sensor has been “null” adjusted. Attach calibration adapter and flow span gas for approximately 2-minutes. Enter

“1233” for channel-1 or “2233” for channel-2 and the internal service display will indicate

“CH-1” or “CH-2”. Next depress push-button “2”. The internal display will indicate “SPan” and adjust the circuit to the concentration of span gas entered.

Note-1: If visual confirmation is desired and / or if system in question does not have front door digital display, the user can view the gas value by depressing “3331”, immediately after the display goes blank. The value will be indicated indefinitely until cleared by depressing push-button “2”. Use push-buttons “1” and “3” to toggle between the channels.

Note-2: A sensor will not span adjust unless the sensor response is above “5” . d) AUTO-CAL (AUTOMATIC): “1131” AND “2131”

This function allows the user to perform a fully automatic calibration procedure on each sensor. Note: prior to performing an “Auto-Cal” function, ensure that the concentration of span gas has been entered. Attach the calibration adapter and flow zero emissions air over the sensor for approximately two minutes. Enter “1131” to enter channel-1 auto-cal function.

The internal service display will indicate “CH-1” briefly, then “CAL” for approximately 5 seconds, then “null” for approximately 5 seconds, then “SPAn”. At this point, remove the zero emissions air, attach the cylinder of span gas and start flowing gas over the sensor. After the microprocessor recognizes that the sensor has started responding to the span gas (minimum

“5”), the internal display will indicate the concentration of gas as the sensor responds to it.

Also, at this point, the microprocessor starts a 2-minute count down to gas flow. At the end of this count down, the internal display will indicate “donE”. Remove span gas, the calibration function is finished. Results are automatically saved to the sensor module. If the system in question has two sensors, repeat the procedure for channel-2 sensor by entering “2131”. e) SENSOR DEFAULTS: “1123” AND “2123”

This function allows the user to reset the sensor / transmitter to factory defaults if it gets to a point where sensor code changes are not being accepted. After setting the transmitter board to factory defaults, the user must re-program it. To set to factory defaults for channel-1, enter

“1123” and depress push-button “2” to accept. To set to factory defaults for channel-2, enter

“2123” and depress push-button “2” to accept. WARNING: All calibration data will be lost

when activating sensor defaults. Sensors must be re-calibrated.

10.0 MENU FUNCTION ITEMS, CONT’D..... f) SENSOR TYPE: “1231” AND “2231”

This function allows the user to set the parameters for a specific type of sensor. Eg. NO2 sensors produce a reverse moving signal in the presence of gas and thus requires a different sensor code than CO which produces a forward moving signal in the presence of gas. This function also allows the user to fit a different gas sensor to a specific channel. This value is written to the sensor transmitter circuit board memory. g) DECIMAL SET: “1122” AND “2122”

This function allows the user to add up to three decimal points to values indicated on the displays. To achieve this, enter “1122” for channel-1 and the internal service display will indicate the number of decimal points currently being displayed. To change this, depress push-button “1” to decrement the number or push-button “3” to increment the number. Press push-button “2” to accept the change and the internal display will indicate “donE”. Repeat the above procedure, depressing “2122” for channel-2. Remember to depress “2” to accept any changes that have been made. h) OVER FLOW THRESHOLD: “1311” AND “2311”

This function sets the maximum measuring range. Default is “1000” for all sensors. When the sensor response exceeds this value, the display will indicate “OFL” (over flow). i) UNDER FLOW THRESHOLD: “1312” AND “2312”

This function sets the point at which a negatively drifting sensor is considered in fault or under flow. The display will indicate “UFL”. Factory default is “-25” (if decimals have been programmed, the value will be displayed as “-2.5” , “-.25” or “-.025”). j) POWER UP WARM UP: “3311”

This function sets the count down, warm up time period for a system. Factory default is 120 seconds (2-minutes). Sometimes when performing some types of service work, a system may have to be powered down momentarily. To facilitate a quicker restart, set the warm up time to 5 or 10 seconds before powering down the system. Remember to reset to “120”.

Note: This parameter is stored in the Channel-1 sensor circuit. k) LOW ALARM SET: “1211” AND “2211”

All SCD systems are supplied with standard factory alarm set points that can be changed in the field if required. Changing the alarm set points is a completely independent function from calibration and therefore calibration values will not be altered in anyway. To change the low alarm set point, enter “1211” and the internal service display will indicate the alarm set point value for channel-1. To change this value, simply depress push-button “1” to decrease the value or push-button “3” to increase the value, then depress push-button “2” to accept. The display will indicate “donE”. Hold push-buttons for 2 seconds to scroll value quickly, up or down. Repeat the above procedure, depressing “2211” for channel-2 low alarm set point.

Remember to depress “2” to accept any changes that have been made. l) HIGH ALARM SET: “1213” AND “2213”

Follow the procedure outlined in “k)” above but enter “1213” for channel-1 or “2213” for channel-2 to display and / or change the system high alarm set points. Again, remember to depress “2” to accept any changes that have been made.

10.0 MENU FUNCTION ITEMS, CONT’D.....

m) RELAY SENSE: “3312”

“Relay sense” function allows the user to change the state of the system alarm relays. The system relays are shipped from the factory in “fail-safe” mode (normally energized in non gas alarm state). Fail-safe state is indicated by the illumination of the amber LED light indicator beside each relay. To change this to “reverse” mode (not normally energized in non gas alarm state), enter “3312”, the internal service display will indicate “FS-y” (fail-safe yes). To change the relay state, depress push-button “1” and the display will indicate “FS-n” (fail-safe no). Depress “2” to accept the change. At this point, an audible “click” can be heard as the relay coils are de-energized and the amber LED light indicators, beside the relays, are no longer illuminated. n) 4-20 mA LOWER RANGE: “1321” and “2321”

This function allows the user to set the lower signal output range that will represent 4.0 mA

Factory default is “0”. To change this value, input “1321” and the display will indicate the current value. To change this, simply depress push-button “1” to decrease the value or pushbutton “3” to increase the value, then depress push-button “2” to accept.

Repeat the above procedure, depressing “2321” for channel-2, 4-20 mA lower range.

Remember to depress “2” to accept any changes that have been made.

Note: Because this range is user adjustable, the lower range can be set higher, for some custom applications. Example: The 4.0 mA could be set to match the low alarm set point so the user would have a signal that started at the low set point and ranged upward to 20.0 mA. o) 4-20 mA UPPER RANGE: “1322” and “2322”

This function allows the user to set the UPPER signal output range that will represent

20.0 mA Factory default is “200”. To change this value, input “1322” and the display will indicate the current value. To change this, simply depress push-button “1” to decrease the value or push-button “3” to increase the value, then depress push-button “2” to accept.

Repeat the above procedure, depressing “2322” for channel-2, 4-20 mA upper range.

Remember to depress “2” to accept any changes that have been made. p) VALUE DISPLAY: “3331”

This function allows the user to display the value of each channel on internal service display. Enter “3331” and the value of channel-1 will be displayed. To view channel-2 value, depress push-button “3”. The value will be indicated indefinitely until cleared by depressing push-button “2”. q) TOGGLE RELAYS: “3132”

This function allows the user to literally “toggle” the relays, (de-energize, then energize the relay coils, assuming they are in fail-safe state). Enter “3132”, the internal service display will indicate “ON”. To toggle the alarm relays, depress push-button “1” momentarily. The internal display will indicate “OFF”, an audible “click” can be heard as the relay coil de-energizes and the amber LED light indicator beside the relays will no longer be illuminated.

cont’d next page…..

10.0 MENU FUNCTION ITEMS, CONT’D.....

To toggle the high alarm relay, depress push-button “3” momentarily. The internal display will indicate “OFF” an audible “click” can be heard as the relay coil de-energizes and the amber LED light indicator beside the relay will no longer be illuminated.

Depress push-button “2” to exit this function. The relays always return to the default state. r) SCD DEFAULTS: “3123”

This function allows the user to reset the SCD mother board to system defaults if problems are experienced that cannot be overcome with programming. Input “3123” and depress “2”. The default settings include: high and low set-points, 4-20 mA range, relay sense to fail-safe, upper and lower calibration limits for the 4-20 mA output module.

Note: If the user enters a code by mistake and wants to abort the routine, simply depress “1” and “3” push-buttons at the same time. If the user is in the middle of a calibration routine and decides to abort it, the updated null value will be stored and the span value from the last calibration routine will be retained.

11.0 SYSTEM MAINTENANCE

The SCD series system requires virtually no maintenance other than regular calibration of the integral or remote sensor and ensuring that excess water or dust is not somehow entering the enclosure and physically damaging the circuit board or internal components.

11.1 CALIBRATION PROCEDURE

Tools required: CETCI calibration kit containing a selection of calibration flow adapters, cylinder flow regulator (fixed flow rate of 0.2 to 0.5 LPM) and cylinders of clean (zero emissions) air and calibration span gas.

All SCD circuits will utilize an “auto-cal” function, meaning, calibration “null” and “span” functions are achieved automatically through functions of the circuit software and without adjusting any potentiometers. Three small push-buttons are located on the main circuit board along with an internal service digital display. These buttons are used to access a wide range of user selectable functions, including activating the “auto-cal” function. Please refer to the table located on page 34 for a list of all menu codes. a) Calibrating Oxygen Sensors:

Because Oxygen sensors are detecting the target gas almost 100% of the time, the response to changes in Oxygen concentrations is usually “downward”. For this reason, calibration must be achieved with a slightly different procedure. Please follow the directions listed below:

1. Span gas value: Ensure that the concentration of Oxygen span gas has been entered as

“20.9”. Enter “1132” for CH-1 and “2132” for CH-2.

2. Null set (manual): This part of the procedure is required when a new sensor has been installed. Flow 100% Nitrogen (N2) over sensor for approximately 2 minutes, before adjusting null. Enter “1133” for CH-1 or “2133” for CH-2. Depress push-button “2” and the display will indicate “null”. Allow sensor approximately 5 minutes to recover from the Nitrogen before proceeding with the next step.

11.1 CALIBRATION PROCEDURE, CONT’D.....

3. Span set (manual): Expose sensor to ambient air or a source of 20.9% volume Oxygen.

Enter “1233” for CH-1 or “2233” for CH-2 to achieve span adjustment. The inner display will indicate “CH-1” or “C-2”. Next depress push-button “2” and the display will indicate “SPan” and the reading will be adjusted to “20.9”. b) Calibrating Toxic or Combustible Sensors

Push-button calibration can be achieved in two ways. a) One button access “auto-cal”. b)

Manual access to both “auto null” and “auto span”. Both versions are described below.

Note: Prior to performing either calibration function, ensure that the concentration of span gas has been entered (codes 1132 and 2132) and each sensor has been “null” adjusted

(codes 1133 and 2133) in a relatively gas free environment.

1) Auto-cal: To begin calibration, attach cylinder flow regulator to cylinder of zero emissions air and attach appropriate flow adapter to end of flow hose. Attach flow adapter to integral or remote sensor. Open regulator and flow zero air over sensor for approximately 2 to 3 minutes. Optionally, attach calibration adapter plug and fit both opaque coloured plugs onto the inlet and outlet ports. Allow sensor to stabilize for 2 to 3 minutes. Next, follow the procedure as described in section 10.0 d) on page 32. See Note-3 below for more details.

2) Manual calibration: To begin calibration, attach cylinder flow regulator to cylinder of span gas and attach appropriate flow adapter to end of flow hose. Attach flow adapter to integral or remote sensor. Next, follow the procedure as described in section 10.0 c) on page 32.

When calibration procedure is finished, remove cylinder regulator from cylinder of span gas for storage. Note date and details of calibration for future reference.

Note-1: When calibrating Oxygen sensors, null adjustment must be carried out with 100%

Nitrogen (N2) flowing over sensor. Span adjustment can be achieved with clean ambient air as an alternative to cylinder zero air or Oxygen. If using clean ambient air, avoid exhaling in the direction of the sensor while making span adjustments.

Note-2: Remove sponge from humidification chamber when calibrating all electrochemical sensors and solid-state Ammonia sensors. Sponge must be used when calibrating solid-state combustible sensors and solid-state refrigerant sensors.

To use sponge, thoroughly wet with water. Next, grasp sponge with thumb and three fingers and squeeze out excess water until sponge no longer drips. Insert sponge into center of humidification chamber, ensuring it does not block the flow of gas on either end of the chamber. Snap the cap back onto the end of the humidification chamber and ensure a tight fit to prevent span gas from escaping.

Note-3: Zeroing plug works better than zero emissions air on some brands of Nitrogen

Dioxide (NO2) and Chlorine (Cl2) sensors. Important: remember to remove both plugs prior

to flowing span gas.

11.2 CALIBRATION SET-UP DRAWING

MODEL “SCD” TWO SENSOR

CONTROLLER, SHOWN WITH

ONE INTEGRAL

ELECTROCHEMICAL CO SENSOR

AND ONE REMOTE SOLID-STATE

DIGITAL PROPANE SENSOR /

TRANSMITTER.

NOTE: HUMIDIFICATION

CHAMBER REQUIRED ONLY

WHEN CALIBRATING SOLID-

STATE SENSORS

GAS FLOW HOSE

CALIBRATION ADAPTER

CYLINDER REGULATOR

WITH PRESSURE GAUGE

HUMIDIFICATION CHAMBER

CARBON

MONOXIDE

(CO) SPAN

GAS

GAS CYLINDER

PROPANE

(C3H8) SPAN

GAS

GAS FLOW HOSE

MODEL “RDS” REMOTE

DIGITAL SENSOR /

TRANSMITTER

12.0 TROUBLE SHOOTING TIPS

a) Recovering from “UFL”: The quickest way to recover from underflow is to null adjust the sensor in question.

If specific problems are experienced that have no trouble-shooting tip listed above, contact

CETCI for assistance.

13.0 REPLACEMENT / SPARE PARTS LIST

DESCRIPTION PART NUMBER

Main PCB 752-SCD0-11

RDS remote smart sensor solid-state PCB 752-RDS0-11

RDS remote smart sensor electrochemical PCB 752-RDS0-21

SCD PVC enclosure non-display 770-SCD0-11

SCD PVC enclosure non-display remote 770-SCD0-21

SCD PVC enclosure display 770-SCD0-31

SCD PVC enclosure display remote 770-SCD0-41

SCD operation / instruction manual 702-SCD0-11

SCD microprocessor ic 751-SCD0-11

SCD display microprocessor ic 751-SCD0-21

Urethane sensor shroud Ind electrochemical sensors PVCSenFLG

Urethane sensor shroud solid-state sensors PVC SenHSG2

Electrochemical HVAC CO sensor SEC-7000-MCO

Electrochemical Industrial CO sensor SEC-7000-CO

Electrochemical NO2 sensor SEC-7000-NO2

Electrochemical Chlorine sensor SEC-7000-CL2

Electrochemical Ozone sensor SEC-7000-O3

Electrochemical Ammonia sensor SEC-7000-NH3

Electrochemical Nitric Oxide sensor SEC-7000-NO

Electrochemical Hydrogen Sulphide sensor SEC-7000-H2S

Electrochemical Sulphur Dioxide sensor SEC-7000-SO2

Electrochemical Hydrogen sensor SEC-7000-H2

Electrochemical Ethylene Oxide sensor SEC-7000-ETO

Electrochemical Oxygen sensor SEC-7000-O2

Solid-State Combustibles sensor SEF-8000-CB

Solid-State Ammonia sensor SEF-8000-NH3

Solid-State Refrigerants R0 sensor SEF-8000-R0

Solid-State Refrigerants R1 sensor SEF-8000-R1

Solid-State Refrigerants R2 sensor SEF-8000-R2

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Key Features

Programmable microprocessor
User-adjustable time delays
LED display option
4-20 mA output signal
Remote sensor compatibility
Audible and visual alarms
Fail-safe relays
Automatic calibration
Easy to install

Frequently Answers and Questions

Can I use this gas detector in a hazardous area?

No, this instrument is not designed to be intrinsically safe. It should not be used in classified hazardous areas (explosion-rated environments).

What is the warranty on the gas detector?

Critical Environment Technologies Canada Inc. warrants this instrument to be free from defects in materials and workmanship for a period of two (2) years from the date of purchase. Individual sensor elements have different warranties.

How do I calibrate the gas detector?

The calibration procedure is outlined in the “Calibration Procedure” section of this manual. It involves using zero emissions air and a known concentration of span gas to adjust the sensor readings.