Parker ABG35S Series, VRD350 Series Installation Manual

Bulletin HY11-AL287-M1/UK

Installation Manual

Series VRD350, VRD355, ABG35S

Digital

Power Amplifier

Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Gutenbergstr. 38

41564 Kaarst, Germany

Tel.: +49-181 99 44 43 0

Fax: +49-2131-513-230

E-mail: [email protected]

Copyright © 2003, Parker Hannifin GmbH & Co. KG

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

IA VRD UK.INDD RH 02.06

Note

This document and other information from Parker Hannifin GmbH, its subsidiaries, sales offices and authorized distributors provide product or system options for further investigation by users having technical expertise. Before you select or use any product or system it is important that you analyse all aspects of your application and review the information concerning the product or system in the current product catalogue. Due to the variety of operating conditions and applications for these products or systems, the user, through his own analysis and testing, is solely responsible for making the final selection of the products and systems and assuring that all performance and safety requirements of the application are met. The products are subject to change by Parker

Hannifin GmbH at any time without notice.

2 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Content

1. Description and Design

1.1. Technical Data

1.2. Ordering Code

1.3. Connection

1.4. Block Diagrams

2. Commissioning

2.1. Front Panels

2.2. Programming

2.3. Signal Diagrams

2.4. Diagnosis

2.5. Parameters

3. Function

3.1. Command signals

3.2. Ramp Function Generators

3.3. Offset

3.4. Valve Curve Linearisation

3.5. Adjustment of Current Gain

3.6. Dither

3.7. Current Controller

3.8. Output Stages

3.9. Step Functions

3.10. Control Circuits

3.11. Zero Point Adjustment

3.12. Controller Parameter

3.13. Programmable Comparator Function

3.14. Serial Interface

3.15. ABG35S

4. Operating and Error Messages

4.1. Enable

4.2. Reset Ramp

4.3. Malfunction and Error Messages

4.4. Comparator Output

4.5. Externally selected command signals and directions

5. Wiring Diagram of Rear Connector

6. Parameter List

7. Wiring Diagrams

Page

24

31

32

32

26

26

26

27

25

25

25

25

24

24

25

25

33

33

33

33

34

34

34

35

37

4

7

9

5

6

12

12

13

15

20

20

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Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

1. Description and Design

Applications (general)

Amplifier card for driving proportional directional valves, pressure and flow control valves. Suitable for solenoid systems up to 3.5 A. Valves with spool position feedback, and external closed loop control circuits (e.g. pressure regulating circuits) can be implemented with the closed loop control options.

Suitable for use on NC axes, especially where the requirements for dynamic response and accuracy are high.

Special Application of VRD355

Amplifier card without the front panel display and operating elements for cost effective applications where operation is via a serial interface or ABG35S

(must be ordered separately, No. 23.501 456).

The VRD350 / VRD355 Series is distinguished by the following Features:

• PWM output stage with programmable current controller.

• Adjustable parameters for all solenoid types up to 3.5A.

• Digital setting and display of all parameters.

• High set value and feedback resolution

(<0.05%).

• No temperature or long-term drift.

• Precisely reproducible settings.

• Serial interface on the front panel for remote parameter setting.

• Simple operation by 4 entry keys and 3-digit

LED display.

• Fault indication by numeric code.

• Variable dither amplitude and frequency.

• Gain for solenoids A and B can be set independantly.

• Different valve characteristics are stored on-board to enable linearisation.

• Set value simulation for simplified commissioning.

• Only a unipolar supply voltage is necessary

(24V).

• Internally adjustable time delay of output stages after applying the enable signal.

• Integrated actual value recording.

• Robust, SMT technology.

• Differential amplifier input for NC command signal 0...±10V.

• Additional input for command signal specification by 0...±10V.

• Integrated power supply for ±10V symmetrical to 0V supply, each capable of carrying 10mA.

• 4 recallable command signals.

• “+” and “-”-direction externally set.

• Enable signal for output stages.

• Reset-Ramp for quick reset of ramp function.

• All external input signals for command signals, direction, enable, reset ramp are electrically isolated by opto-couplers.

• Status outputs “Error” and “Comparator” are similarly electrically isolated by opto-couplers.

• Function indication by LEDs on front panel.

• In addition, for simpler commissioning and for service purposes, test sockets are located on the front panel for S6 (NC-command signal),

A (feedback value, where available), I

(Measurement instruments R i

A

>100k Ω ).

and I

B

Meaning of Symbols

Warning, danger for user.

Attention, possible damage to unit or other capital assets.

Note, information, key function.

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Hydraulic Controls Division

Installation Manual

1.1. Technical Data

General

Design

Electrical

Supply voltage

Current consumption

Power consumption (24V)

Pre-fuse

Inputs

Analogue Feedback value

Feedback value

Feedback value

Feedback value

Feedback value

Feedback value

Command value 5/6

Digital 0

1

Outputs

Ext. supply voltage

Reference

Analogue

Digital

Solenoids

Interfaces

Serial

Adjustment range

Min

Max

Ramp time

Dither Amplitude

Frequency

Zero point

Protection class

Industrial protection class

Environment conditions

Temperature

Connection

Plug connector

Cable dimensions

Cable length

Dimensions

Front panel

Printed circuit board

EMC

EN 50081-2

EN 50082-2

EN 50011

EN 61000-4-2

Digital Power Amplifier

Series VRD350 and VRD355

Europe format

[V] 18...30, ripple < 5%

[A] 3

[VA] 50

[A] 3.15 quick acting

[V] 6 ±2, 600kOhm

[V] 7.5 ±2, 600kOhm

[V] 0...10, > 10MOhm

[V] 0...±10, > 10MOhm

[mA] 0...20, 100kOhm

[mA] 4...20, 100kOhm

[V] 0...±10, > 150kOhm

[V] 0...1

[V] 3...30

[V] 24 ±10%, ripple <5%

[V] +10, -10, 10mA

[V] 0...10, 5mA

[mA] 50

[A] 0.8 / 2.7 / 3.5

RS 232C

[%] 0...100

[%] 0...100

[s] 0...39.5

[%] 0...30

[Hz] 0...647, in steps

[%] -30...+30

IP00

[°C] 0...50

DIN 41612, 48pin design type F

AWG 15 (power supply + solenoid); 20 (all others)

[m] max 50

[mm] 50.5 x 128.4, 10TE/3HE

[mm] 100 x 160

EN 61000-4-3 EN 61000-4-4

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Hydraulic Controls Division

Installation Manual

1.2. Ordering Code

VRD

Digital

Amplifier for

Proportional

Valves

Module

Code

350

355

Module with front plate display / and operating elements without front plate display / and operating elements

Type

Code

0

1

Type controlled regulated

Code Solenoid type

1 0.8A

3

5

7

2.7A

3.5A

2.7A

(RLL-central threaded solenoid)

Code

0

1

Solenoid / sensor version

Flange solenoids

(or. pos. transducer with 6V (zero voltage)

Central threaded solenoids (or position indicator with 7.5V null voltage)

Digital Power Amplifier

Series VRD350 and VRD355

Solenoid

Type

Solenoid/

Sensor

Type

Function Sensor

Assignment

External

Closed

Loop

Design

Series

Code

-

R

Function controlled regulated

Code Ext. closed loop*

0 without

0

1

0...±10V

4...20mA

2 0...20mA

* The values for actual value signals apply to directional valves.

Code Sensor assignment

0 1) controlled

1 2) Flow valves NG6

2 2) Directional valves NG6

3 2) Directional valves NG10

4 2) Directional valves NG16

5 2) Directional valves NG25

6 2) Directional valves NG32

7

8

9

1)

1)

2) ext. closed loop

(DC valves) ext. closed loop

(press./flow valves)

Directional valve

D91FS

1) without feedback on valve

2) with feedback on valve

Assignment Table

Proportional DC Valves

Type

DC Valves

Pressure

Valves

Flow Valves

Description Solenoid

D*1FW

D*1FS

RLL

WLL

WLL

VB

VBY

VMY

DUR

—

—

—

—

—

L

L

G09

G09

Size

10...32

10...25

6

6

10

6

6...10

6...10

6 without position transducer

VRD35*-030-00

Amplifier card for valves with position transducer

— w/o pos. transducer, with ext. closed loop

VRD35*-130-R7*

—

VRD35*-071-00

VRD35*-130-R*0

VRD35*-171-R20

—

VRD35*-171-R7*

VRD35*-031-00

VRD35*-050-00

VRD35*-010-00

VRD35*-010-00

VRD35*-010-00

VRD35*-010-00

VRD35*-131-R20

VRD35*-150-R30

—

—

—

VRD35*-110-R10

VRD35*-131-R7*

VRD35*-150-R7*

VRD35*-110-R8*

VRD35*-110-R8*

VRD35*-110-R8*

VRD35*-110-R8*

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Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

1.3. Connection

Connect unit in accordance with terminal connection diagram on page 9. The supply voltage for the unit at terminals 26bd = 0V and 32bd = + U

B to 30VDC, residual ripple ≤ 10%.

is 18V

Output stages are electronically protected against short circuit and excess current. The amplifiers should be protected with a quick-acting preliminary fuse (see technical data). Connection of solenoids is made at teminals 22bdz and 28bdz for solenoid

A, terminals 24bdz and 30bdz for solenoid B. Terminals bdz are bridged on the amplifier. Connection should, however, be made to all three terminals on account of the current carrying capacity.

If no electrical isolation of the logic inputs or outputs is required, terminal 26bd must be bridged to terminal 2d and terminal 32z to terminal 32bd.

The following devices are to be regarded as strong sources of interference:

• Switching power supply units

• Frequency converters

• Drive modules

• Mains filters with wiring (even if screened)

• AC/DC commutator motors

• Motor cables (even if screened)

• Switched inductances, even when anti-interference measures have been taken (solenoid valves, contactors, relays, brakes, etc.) trained personnel should work with the unit. All safety instructions must be observed. If the card is disconnected whilst the power supply is still damage may result. Avoid such actions at all cost.

General

The assembly contains electronic components. Incorrect handling or operation can lead to damage through electrostatic discharge (ESD). Only

Devices from the VRD350/VRD355 series are class

A equipment and thus only suitable for industrial surroundings.

The distance between a source of interference

(device emitting interference) and an interference sink (a device under the influence of interference) is of decisive importance. The interfering field of the source reduces the greater the distance between this and the sink. In other words, the closer a device is placed to a source of interference, the greater the incidental amplitudes. For this reason, there should be a minimum gap of 0.25 m between the amplifiers and strong sources of interference.

One of the most common input points is the wiring.

This influence can be minimised. Interfering cables should therefore be laid at least 0.25m away from cables susceptible to interference. Parts of the amplifier wiring may be susceptible to interference

(command signal, actual value, solenoid cables, etc.). Parallel laying of cables is very critical. The necessary distance has to be increased if cables are laid parallel over longer distances (> 10 m).

The influence is least when cables cross, particularly if this is at an angle of 90°. Nor should cables susceptible to interference ever be laid parallel to motor cables, in particular over longer distances, and must always cross these at an angle of 90°.

However, interference can also arise from cables in the amplifier wiring system, in particular solenoid cables.

Examples of devices which are particularly susceptible to interferences:

• Office PC’s

• Sensors with small output voltages

• Proximity switches (capacitive)

• Audio equipment (TV, Hi-Fi, radio, etc.)

• Devices which do not comply with EMC guidelines.

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Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Special Notes on Wwiring and Electrical Cabinet Design

The following rules and tips by no means claim to be complete. Since various electronic components are used in a variety of different ambient conditions, these guidelines only represent a compromise. The actual design of the wiring also depends on the interference emission and resistance to jamming of the individual components.

• Use screened and twisted pairs of cables for the solenoid connections. The screen must be earthed (PE) at both ends. The capacity should be 120pF/m. Cables must be ≥ 1.5mm² for a length up to 100m and ≥ 2.5mm² for a length over 100m.

• Digital signal lines are to be connected at both ends to PE with a good conductivity. Command signal and actual value connections should have screened and twisted cables. These analog signal lines are to be connected to earth at both ends with a good potential equalisation.

The screen connections should be made over a large area.

• In environments with great interference, use doublescreened cables for command signal and actual value connections. The inner screen is only earthed at one end, the outer screen at both ends.

• In the event of low-frequency interferences on the analog signal lines (measured value fluctuations), the screen should be connected at one end. However, a corresponding potential equalisation is preferred. (See also following point)

• The reference point for command signal and actual value signals is analog 0V (terminal 26z).

All setpoint and actual value transmitters are to be connected to this terminal so as to avoid zero shifts and incorrect measurements.

• When replacing older devices, the non-fused earthed conductor (PE) should be connected to terminal 18d or 18b. If ripple voltages occur, connect 16b or 20b to PE. In this case the connection to 18bd must be removed. (But: preferably make a potential equalisation!)

• Use only cables with a Cu screening grid and a covering of > 85% whenever possible. Avoid screening films.

• The screen may not be interrupted along the entire length of the cable. If contactors, safety switches, chokes, etc. have to be used in the wiring, the installation of a metallic housing with a high HF attenuation may be necessary.

• Screen terminals are to be connected over a large area to the screen rail.

• The screen rail is to be installed close to the cable duct in the electrical cabinet.

• The metallic parts of the electrical cabinet are to be connected with high conductivity on large areas. Avoid painted surfaces. Make the desired connection with mechanical aids such as scratch plates if necessary. The doors are to be connected to the cabinet via the shortest possible homogeneous tapes (multiple).

• Solenoid valves, contactors, relays, brakes, etc., are to be suppressed directly at the respective coil. Suitable suppression devices are, for example, RC networks, diodes or varistors.

• Analog and digital signal lines should preferably enter the electrical cabinet from one side.

• Unscreened lines of an electric circuit are to be twisted.

• Auxiliary wires are to be earthed at both ends.

• Avoid unnecessarily long lines. This keeps the coupling inductances and capacities small.

• Wiring should preferably not be free in the cabinet. Cables, including auxiliary cables, should be laid as close as possible to mounting plates and the cabinet housing.

• In the event of an inadequate potential equalisation between the screen connections, a balancing conductor > 10 mm² should be laid parallel to the screen to reduce the screen current. A multiple connection of the screen to the cabinet casing and thus PE is generally possible. A multiple connection of the screen is also permissible outside the cabinet.

• If filters are fitted, these should be installed close to the source of interference and with a good surface contact on the cabinet or mounting plate.

• If converters are used, converter filters must be provided. Variable speed motors may have to be connected using screened lines.

• All further instructions of the converter manufacturer are to be observed.

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Hydraulic Controls Division

Installation Manual

1.4. Block Diagram; Entire System

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Feedback Option

(hardware, only with boards for closed loop systems)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Jumper Field for Actual Value Input

Digital Power Amplifier

Series VRD350 and VRD355

Classification of Application Cases

• Voltage input with terminating resistance R =

600kOhm:

Used for all proportional valves with displacement transducers with mean voltages 6V and 7,5V.

Terminal Connection Diagrams for the Standard

Feedback Transducers for Position-Controlled

Valves

Line socket

WLL NG10

Connector assignment

• Voltage input without terminating resistance:

Used for potentiometric transmitter systems in which the loop current is limited to smal values.

Linearity of the transmitter signal is maintained.

• Current input with load R = 100Ohm:

Used for all sensors with current output 0...20mA or 4...20mA.

D*FS, RLL, WLL NG06

1 - Output

2 - Supply (+24V)

3 - 0V

4 - not used

1 - Output

2 - Supply (+24V)

3 - 0V

4 - not used

5 - GND

DUR

1 - Output

2 - Supply (+24V)

3 - 0V

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Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

2. Commissioning

2.1. Front Panels

Front panels of VRD350 and ABG35S are identical.

The only difference is the plug connector for the

RS232 interface (only with VRD350).

Before switching the supply voltage on, the electrical wiring must be checked.

Limit switches must be operational to avoid uncontrolled movements.

Relevant safety regulations must be observed carefully. Suitable emergency stop measures must be taken.

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Application, Construction and Operation of

ABG35S

The ABG35S plug-in control unit is used in conjunction with the VRD355 proportional amplifier.

It can easily be plugged in and removed again when parameters have been set. Combination of the VRD355 and ABG35S provides the optimum solution for price sensitive applications together with ease of operation, especially where a number of amplifier cards are used e.g. for applications in production line machines or multi-axis NC machines. When the ABG35S is removed, unauthorized access to the set parameters is effectively prevented.

No additional components of any kind are required for operation of the ABG35S with the amplifier card.

Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

2.2. Programming

Programming Instructions for U-, S-, P- and E-Values

Select mode

U1, S1, P1 or E1 can be selected

Select address

Display contents

Alter contents e.g.: S2 has the value:

First press key “E“, then press key “M“ simultaneously.

For E-values, press key

“M“ twice.

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Installation Manual

Transfer contents

Digital Power Amplifier

Series VRD350 and VRD355

Value is transfered. The previously selected address appears again.

Programming Instructions for H-Values

(Command Signal Simulation)

Select mode

Select mode U1

Select mode H1

First press key "E", then press key "M" simultaneously.

Select address

Display, alter, transfer contents

H1 or H2

Same procedure as for U, S and P-values. See previous page

Select new address or return to mode U1 with the "M"-key.

After leaving H mode, auxiliary command signals are no longer utilized but remain in the background. They must be set back to zero after commissioning.

After supply voltage is disconnected, H parameter settings are lost.

Basic Settings

All parameters are preset ex-works according to the intended application of the amplifier. This setting depends on the type of amplifier (see also type code). This basic setting can be recovered from memory by pressing the 4 keys at the same time up to 10 seconds after the supply voltage is switched on. During recovery the display shows “HHH“.

Setting parameters does not alter the preset values.

Customized parameters are overwritten by the recovery operation. Further information on adjusting the basic settings can be found in the instructions for the control program PROVRD 350/355.

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Installation Manual

2.3. Block Diagram; Open Loop Control

(Software functions)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Closed Loop

(only with boards for closed loop systems)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

External Closed Loop

(only with boards for closed loop systems)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Remote Loop Control

(only with boards for closed loop systems)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Bypass Controller

(only with boards for closed loop systems)

Digital Power Amplifier

Series VRD350 and VRD355

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

2.4. Diagnosis

Test Sockets

The sockets for I

A

and I

B

can be used to measure the solenoid currents independently. The voltage at the socket is roughly proportional to the solenoid current. The voltage is around 1V at 1A.

At the socket S6 for the sum total of both analog command signals (SW5 and SW6), the measured value appears according to the input signals. At the socket for the actual value (A), the measured value is proportional to the actual value signal. The measured value is analogous to display U11.

Internal Diagnostic Parameters (U-Parameters)

Internally computed values can be displayed on the

7-segment display during normal operation and to aid commissioning and trouble shooting. Values should be interpreted as voltage or current with a resolution standardised in the display at 10mV to

9.99V. The relevant position in the software functions can be taken from the block diagrams. For version:

This is only an auxiliary function. Precise measured values, comparable with a multimeter, are not possible for technical reasons.

The following values are available in the basic

2.5. Parameters

Only trained staff should make parameter changes. The drive should be switched off whilst adjusting parameters.

S-Parameters

Command signals and ramp times are adjusted by means of S-Parameters. They may be set during normal operation and the alteration is immediately effective.

S1...S4

Command signals as voltage

Ramp times in seconds

S5...S8

(increment 0.01s)

(increment 0.1s)

S5 Ramp from 0 to -

S6 Ramp from - to 0

S7 Ramp from 0 to +

S8 Ramp from + to 0

Display

0...9.99V

0...9.99s

10...39.5s

(A-Solenoid)

(A-Solenoid)

(B-Solenoid)

(B-Solenoid)

H-Parameters (auxiliary parameters)

Parameters H1 and H2 are used in the commissioning phase or in test and measurement sequences for simple input of command signals (command signal simulation). This allows a command signal to be input independent of external inputs (command signal 5/ command signal 6 or selection of S1 to

S4 and a direction), without requiring additional external circuitry.

U1 Command signals

U2 Value after the ramp generator

U3 Value after the linearisation table

U4 Value after amplifier gain adjustment

U5 Signal to solenoid A

U6 Signal to solenoid B

U7 Solenoid A current

U8 Solenoid B current

U9 Total current solenoid A + solenoid B

Display in V

Display in mA or A

Further outputs are available with the feedback option card:

U10 Command signal, reference input variable

U11 Feedback value controlled variable

U12 Control difference (error)

U13 Controller output (correcting variable)

Note

Parameter setting and diagnostics only possible for VRD355 using ABG35S.

Display in V

The enable signal must be present so that the output stages are active and current can flow.

Parameters can be set during operation. Any alteration with ⇑ and ⇓ is immediately effective. The polarity sign shows which of the two output stages or solenoids the command signal acts on.

Positive sign

Negative sign

Solenoid B

Solenoid A

All command signals are also additive in the H mode. This means that when command signals are input (internally S1 to S4 and externally SW5 to

SW6), these are added to active H-parameters, taking into account the signs. By switching over from H

1 to H2, or the reverse, it is possible to switch over to different values - also with opposite sign.

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

On leaving the H mode, H parameter values are no longer evaluated and thus are deactivated.

However, H parameter values are also internally stored after leaving the H mode.

When H mode is selected again (always

H1 first), this is immediately effective, with its corresponding value. It is recommended, therefore, that H1 and H2 parameters are set to 0.00 when commissioning has been completed. The H-parameters are set =

0.00 when the supply voltage is switched off.

H1...H2

Command signal simulation

Command signals as voltage

Display

0...±9.99V

P5 Dither amplitude of 0...30%; a setpoint of 3 V corresponds to 30 % see also page 25, section 3.6)

P6 Dither frequency variable in steps from 0 to 647 Hz

(steps: 0, 16, 40, 60, 80, 110, 130,

160, 220, 327, 647 in Hz)

(See also page 25, section 3.6)

P7 Step function for solenoid A

(See also page 26, section 3.9)

P8 Step function for solenoid B

(See also page 26, section 3.9)

* Max. depending on solenoid type

0.8 A; 2.7 A or 3.5 A

Display

0.00...3.03 V

0.00...max. *

0.00...max. *

The display’s resolution is lower than the input resolution. This is why only every 2nd ... 4th key actuation leads to a change in the display.

P-Parameters

Parameters can be set during operation. Any alteration to P-Parameters with ⇑ and ⇓ keys is immediately effective. These parameters allow the amplifier unit to be matched to the valve or the drive.

The drive should be switched off whilst adjusting parameters.

On pages 35 and 36 all P- and E-parameters are listed with their default values. Display of sign, see page 34.

P1 Offset (+30%... -30%)

(See also page 25, section 3.3)

Steps in 5 mV

Display in 10 mV steps

P2 Linearisation

Not active

Active when using NC, select a linearisation!

(See also page 25, section 3.4)

P3 Gain factor for solenoid A

(See also page 25, section 3.5)

P4 Gain factor for solenoid B

(See also page 25, section 3.5)

No solenoid current output is possible with P3, P4 = 0.00.

Display

0.00...+2.99

0.00...-2.99

0

1...5

0.00...2.00

0.00...2.00

Display

P9, P10 Initial current for solenoid A and B, values in in mA

0.8A solenoid

2.7A solenoid

3.5A solenoid

-205...+183

-704...+630

-917...+821

Initial currents are necessary with directly operated directional valves NG6 and NG10 with spool position transducers to ensure correct measurement of displacement.

Display

P11 Command signal not inverted inverted

Also available with the closed loop version:

1

-1

P12 Actual value not inverted inverted

P13 With E2 = 1, 2, 4:

P-portion (K

P,1

) for control deviation ≤ threshold (P15)

With E2 = 3:

P-portion (K

PBP

) bypass-loop

P14 T-portion of PT

1

(affects P16)

-element

P15 With E2 = 1, 2, 4:

Threshold for switch over to K

P,2

With E2 = 3: not active

Display

1

-1

0...255

0...255

0...255

0.00...9.99V

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

P16 With E2 = 1, 2, 4:

P-portion (K

P,2

) for control deviation > threshold (P15)

With E2 = 3:

P-portion of PID-controller (K

P

P17 I-portion

)

P18 D-portion

P19 T-portion of DT1-element

(affects P18)

P20 Gain for actual value input

Display

0...255

0...255

0...255

0...255

0...255

0.00...2.00

Parameter for comparator function and remote loop control:

P21 Comparator value

(positive)

P22 Comparator value

(negative)

P23 Time for switch-on delay

P24 Time for switch-off delay

With E14 = 0 or 1

With E14 ≥ 2

With E14 = 0 or 1

With E14 ≥ 2

With E2 = 3

K

I

K

D

Display

0.00...9.99V

0.00...9.99V

0.00...9.96s

0.00...9.96s

With P21 and P22 = 0.00 the comparator is switched off.

With E2 = 2 (remote loop control), P21 and P22 have a different interpretation.

Conversion factors for controller parameters:

K

P13

= [P13] / 64

K

P13

= [P13] / 64 * E14

K

P16

= [P16] / 64

K

P16

= [P16] / 64 * E14

K

P13

= [P13] / 255

([P17] / 1024) / 0.75ms

([P18] / 16) * 0.75ms

E-Parameters (Extended Parameters)

For general setup of the amplifier which does not have to be altered during normal operation. The

E-parameters are factory preset. Any changes have no effect before the values have been stored using the E-key.

Display

E1 Reserved

E2 Closed loop control

(only with boards for closed loop systems)

• not active

• active

• remote loop control

• bypass control

• safety function active (only with E14 = 1)

E3 Solenoid type

0

1

2

3

4

3.5A / (9V) / solenoid coil = 1.8

Ω reserved

2.7A / (9V) / solenoid coil = 2.1

Ω reserved

0.8A / (24V) / solenoid coil = 21 Ω reserved

2.7A / (9V) / solenoid coil = 2.1

Ω

(only for RLL valves)

E4 P-portion current controller energisation

E5 I-portion current controller energisation

E6 P-portion current controller de-energisation

E7 I-portion current controller de-energisation

E8 Ramp change

(for value alteration use S-parameters)

• constant rise rate

• constant time rate (only valid for in-

ternal set values 1...4)

E9 Time delay for enable signal

(0...10s)

1

2

3

4

5

6

7

0...255

0...255

0...255

0...255

1

0

0.0...9.96s

E10 Reserved

E11 Type of feedback transducer

(only with boards for closed loop systems)

7.5V ± 2V (E12 = 1 possible)

4...20mA (E12 = 1 possible)

0...20mA

0...10V

6V ±2V (E12 = 1 possible)

0V ±10V

4...20mA (E12 = 1 possible)

0...20mA

0...10V

1

2

3

4

5

6

7

8

9

7.5V ±4.5V (E12 = 1 possible) 10*

* or specific customer setting. Please direct inquires to the manufacturer. Type 1 to 6 for control circuits with directional valves (U13 can be positive or negative). Type 7, 8 and 9 for control circuits with pressure regulating valves (U13 only

≥ 0). Depending on the selection E12 is automatically set, however, this can be manually overridden.

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Digital Power Amplifier

Series VRD350 and VRD355

E12 Cable fracture detection

(only with boards for closed loop systems) active not active

E13 Serial interface

(see page, section 3.14) aktiv nicht aktiv

E14 Factor for P13 and P16

(nur bei Kartenausf. für Regelkreise)

P13 or P16 * Factor 1

P13 or P16 * Factor 1

P13 or P16 * Factor 2

P13 or P16 * Factor 4

P13 or P16 * Factor 8

P13 or P16 * Factor 16

Select 0 for internal closed loop, values

1 to 16 for external closed loop. E 14 is automatically zeroed if E2 = 0 or E2 = 3 is set. On the other hand, E2 = 3 can be set if E14 ≥ 1. The factor from E14 then only affects P16 and not P13. The changeover in structure by E14 is carried out.

Display

1

0

1

0

2

4

0

1

8

16

If E14 ≥ 1 and E2 = 3 the safety function is not active.

Also available with amplifier VRD355:

E15 Select load / store for ABG35S

Store data in ABG35S

Load data to amplifier

E16 Activates action selected with E15

Proceeding:

Press button E

The display shows the function selectedpreviously with parameter E15 or

Activate the data transfer:

Press button E (hold pressed) at the same time press button M twice, the display flashes. With the arrow button “up” ( ⇑ ) the display shows "run". After pressing the button E, the transfer will start. The display shows “. . .” for the time of data transfer.

Whilst loading the display shows a “-” for the time of data storing.

At the amplifier VRD355 with ABG35S the following error messages may be shown on the display:

--6 No valid data in the ABG or wrong software version in the ABG

--7 Read error while reading from

ABG

--8 Write or read error (verify)

Display

S...

L...

...S

...L

The data in the ABG have to be compatible with the software version in the amplifier!

Extended parameters E4 to E7 are mainly for factory settings. E11 and

E12 can only be selected for a limited range of other transducer types, please contact the manufacturer. Reserved parameters must be left at their factory default value.

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

3. Function

3.1. Command signals

In the standard setting with P11 = 1 positive command signals activate solenoid B and negative values solenoid A.

Internal Command Signals (S1 to S4)

• Four internal set values (S1, S2, S3 and S4) can be selected with an associated direction “+” or

“-”.

• These inputs are optically isolated and can be selected by means of a programmable controller.

• When electrical isolation is not required, terminal 2d must be bridged by the customer to terminal 26bd and terminal 32z to terminal

32bd.

• If both directions are selected at the same time, none of the selected command signals will be activated.

• If no direction is selected, no command signal will be activated.

• All four internal command signals are controlled by the ramp function generator.

• Command signals are additive and are independent of direction.

• If several command signals are selected at the same time, the total of these command signals is subsequently processed.

• In varying combinations a total of 16 command signals can be selected.

External Command Signal 5 and Command

Signal 6 (SW5 and SW6)

• The command signal inputs 5 and 6 are designed for signals 0...±10 V.

• These setpoints are also passed through the ramp function generator (ramp) if E8 = 1. These are also added to the other setpoints. If E8 = 0 they bypass the ramp function generator and have a direct and undelayed effect.

• The input for command signal 6 is designed as a differential amplifier (within the operating voltage range ±15V).

• The signal for command signals 5 and 6 must be standardised to 10V otherwise the A/D converter is overloaded.

Unused analogue command signal inputs should be suitably bridged to analogue OV.

If the sum total of all setpoints exceeds

9.95V the LED >10V starts to flash.

3.2. Ramp Function Generator S5 to S8

The command signals (S1...S4) are integrated accordingly in the ramp function generator. The ramp time for each change of direction can be set independently. Times of 0...39.5 sec. can be set.

The ramp characteristic is assigned as follows:

The ramp function generator can be switched over from constant rise rate to constant time base with

E8. The ramp function generator can be immediately set to 0 with the reset ramp input (terminal

18 z) (quick stop).

Folowing example is presented to help clarify:

Example: E8 = 0 constant time base

S1 = 8.00V; S2 = 2.00V; S7 = 6.00s

The external command signals SW5 and SW6 bypass the ramp function.

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Example: E8 = 1 constant rise rate

3.3. Offset

S1 = 8.00V; S2 = 2.00V; S7 = 6.00s

Affects both internal command signals

S1 to S4 as well as external command signals SW5 and SW6.

Any drift of the drive can be corrected by the offset parameter P1. This functions as an additional command signal. If the assembly is operated on

NC axes, the positioning can be adjusted to 0. The value changes in steps of 5mV, display shows every second step in 10mV stages.

3.5. Adjustment of Current Gain

Current gain can be set independantly in parameters P3 (negative command signals, for solenoid

A) and P4 (positive command signals, for solenoid

B). (e.g. balancing for differential cylinders)

3.6. Dither

The dither signal can be matched to the valve by parameters P5 (amplitude) and P6 (frequency, stepwise adjustment). The dither signal reduces the hysteresis of spool movement. Generally, low frequency signals are more effective, however they may result in noticeable disturbances (noise, oscillations). Values between 80Hz (for systems with a low natural frequency) up to 327Hz (for systems with a high natural frequency) are recommendable. Sensible values for the amplitude are within the range 0.20V to 1.2V. The dither signal reduces the RMS value of the current noticeably at 10V command signal.

3.7. Current Controller

Each solenoid is driven by a pulse width-modulated signal with rapid de-energisation. The solenoid current is measured and compared with the command signal in a controller with a PI-characteristic.

The controller setting can be adjusted separately for rise and fall in the current through parameters

E4 to E7.

3.4. Valve Curve Linearisation

Five curves are available for linearisation of the flow characteristics of different valves:

Valve curve 1: General NC curve, based on experience.

Valve curve 2: Linearisation of NG6 proportional directional valves with flow characteristic P012 and P020.

Valve curve 3: Linearisation of NG6 proportional directional valves with flow charcateristic P006.

Valve curve 4: Linearisation of NG10 proportional directional valves.

Valve curve 5: Linearisation of proportional pressure valves.

Factory settings should only be changed in exceptional circumstances after consulting with the manufacturer.

3.8. Output Stages

• Output stages of PWM type are used to reduce powerlosses.

• The pulse frequency is approx. 1.35 kHz.

• Output stages are equipped with over ener-gisation and high-speed de-energisation to increase the dynamic response.

• Output stages are designed for solenoids up to

3.5 A.

• The particular solenoid type used is set with parameter E3 without any hardware changes.

• Standard settings are available:

E3 = 1 3.5A solenoid; NG10 proportional directional valves, direct controlled

E3 = 3 2.7A solenoid; NG06 proportional valves, standard

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

E3 = 5 0.8A solenoid; NG06 proportional valves, pressure valves, flow control valves

E3 = 7 2.7A solenoid; NG06 high-response directional valves (RLL)

To distinguish between current and voltage feedback signals, jumper X7 on the feedback option board must be set correctly (see page 11). The shunt has a resistance of 100 Ohms. In case it is necessary to shift the zero level, this can be done by the feedback circuit using potentiometer R12

(not possible for E11 = 3; 4; 6; 8 and 9).

3.9. Step Function

A step-like command signal is added in control loops with spool valves to overcome the control edge overlap. The step function can be adjusted with parameter P7 in the negative range (solenoid

A) and with parameter P8 in the positive range

(solenoid B). Valves overlaps are normally around

10% to 15% of FS. The setting has a decisive effect on the quality of positioning for axis drives. The amplification in the small signal range is essentially determined by the step function. In the case of open loop valves, the preset value is directly applied as a current. In the case of valves with spool position feedback, the step function should be understood as an additional position command signal. The current is then adjusted accordingly to reach the specified position. When changing between open loop and closed loop valves different command signals may be necessary to achieve the same effect.

3.10. Control Circuits

(only with boards for closed loop system)

Feedback Signals and their Adjustment

The control can be activated or switched off with

E2. Feedback signals (0...10V, 0...±10V, 0...20mA and 4...20mA) can be connected to terminal 10d.

For valves with spool position feedback using LVDT, two settings for asymmetric signals are available

(6V ±2V or 7.5V ±2V). The selection of the appropriate signal type is done in the software with parameter E11.

Selections 7 to 9 are for external pressure control loops using pressure control valves with only one solenoid. In these cases, the software limits U13 to the positive range (solenoid B).

Selections 1 and 5 are for valves with spool position feedback using LVDTs (see page 11 for standard connections using directional control valves).

Selections 2 to 4 and 6 are for external control loops using directional control valves and suitable feedback transducers. For selections 1 to 6 U13 can be positive or negative, depending on the difference between feedback and set value. Then, either solenoid A or B is energized.

3.11. To set Zero Point

General Case

Place the feedback transducer in its zero position

(see table 25/1) and set the amplifier to display U11.

Then set the displayed value to zero by adjusting potentiometer R12 (enable must be switched on, remove the solenoid connector). If E11 = 7, 8, 9, no values < 0.000 are shown.

With Position-ControlIed Valves

Set initial currents (P9, P10) and then set E2 = 0

(control system not active). Switch on enable and leave solenoid plug connected. Now bring actual value transducer into zero position and switch amplifier over to display U11. Now set display U11 to zero with potentiometer R 12.

For setting the Range of the Feedback Signal or setting the Feedback Gain

Adjust the feedback signal to its maximum value for the particular transducer type. Set the gain with potentiometer R11 so that display U11 on the amplifier shows 9.90. These basic settings are carried out in the factory for amplifiers ordered according to the model codes. The feedback signal can be inverted with parameter P12, and the set value signal with

P11, to change to a required control sense.

The actual value signal is now available at terminal

10b as an independent „display amplification value“

(e.g. for externally calibrated display functions).

The adjustment is made independantly of the real actual value gain. The following adjustments then should be made:

• Leave maximum value of actual value signal set

(see standardising the actual value signal)

• Now adjust potentiometer R13 so that the desired value is present at terminal 10b (e.g. 6 V for 60 bar).

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26 Parker Hannifin GmbH & Co. KG

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Installation Manual

Sensor Type

7,5 ± 2V

4...20mA

0...20mA

0...10V

6 ± 2V

0 ± 10V

7.5 ± 4.5V

Zero point

7.5V

4mA

0mA

0V

6V

0V

7.5V

Digital Power Amplifier

Series VRD350 and VRD355

Offset Adjustment Input

Signal → U11

7.5V → 0V

4mA → 0V not possible not possible

6V → 0V not possible

7.5 → 0V

Position

E11

1

2 or 7

3 or 8

4 or 9

5

6

10

Position

E12

1

1

0

0

1

0

1

Adjustment

Zero Point

3.9...9.9V

1.2...5.4mA

-

-

3.9...9.9V

-

3.9...9.9V

Adjustment

Range Gain

3.3...13

0.37...1.5

0.37...1.5

0.37...1.5

3.3...13

0.37...1.5

0.37...1.5

3.12. Controller Parameters

When setting parameters P13 and P16, the effect of parameter E2 and E14 must be taken into account. E2 = 1 and E14

= 0 are used for position-controlled directional valves. E2 = 1 or 4 (with security function) and E14 ≠ 0 is selected for external control circuits, depending on the gain required. E14 specifies an additional amplification.

E2 = 1, 2 and 4

P13 is the K

P,1

for smal deviations

P16 is the K

P,2

for large deviations

P15 is the switching threshold K

P,1

→ K

P,2

The division into two amplifications permits stable controller settings, even with large deviations.

E2 = 3

Bypass control activated

P13 is the amplification K branch

PBp

of the bypass

P16 is the amplification K

P controller

(P share) of the PID

P15 has no function

E14 = 0 set.

• Parameter P14 can be used to program a

T-portion (delaying time function element). Effect on P16.

• The integral portion is determined by P17 whilst

P18 is used to set a derivative element. The integral function P17 is limited internally to the maximum value. As soon as this is reached, the

LED “>>1OV“ on the display panel lights up.

• The time for a delayed action D-portion is set with parameter P19.

• It is possible to fine tune the gain for the feedback signal by parameter P20 without changing the hardware settings.

• With external controls, P17 = 0.00 in the basic setting!

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Digital Power Amplifier

Series VRD350 and VRD355

External Closed Loop

The structure of the closed loop is as in the figure on page 17. Other types of loop control, e.g. speed controI for rotational drives, are connected similarly.

The ramp function is useful in external closed-loop systems to avoid overdriving the valve and controller. E.g. in position control loops, the ramps determine the speed of the drive.

Using the equations given on page 22 enables the computation of parameters from the loop gain factor. In cases where these calculations are not applicable, the parameters have to be determined experimentally.

During commissioning and after an e-stop, undesired drive movements may occur. The drives are normally run at a specified speed. This is implemented by the internal ramp functions (S5 to S8).

If the e-stop chain is activated, either the supply voltage or the enable is switched off. If only the enable is switched off, you must pay attention to the safety instructions on page 22! After restarting

(supply voltage or enable on), there is usually a large deviation. This then leads to unwanted movements at the drive. The deviation is the result of the ramp-controlled command signal start from zero.

A specific software function ensures that uncontrolled movements are avoidable. To activate this safety option, following parameter settings have to be programmed:

Avoid instability of the control loop during the experimentation. This may cause damage to the drive or machine.

Precondition: E14 = 1... 6 and E2 = 4

This means, if E14 = 1...16, external control loops are activated.

If E2 = 4 the safety function is switched on. If E2 = 1 and E2 = 3 it is not active.

Sequence with active Safety Function

Action

E-stop activated

Restart and/or apply enable signal and set command signals to 0V.

Input

U

Supply

or Enable

Terminal

32bd

U

Supply

and/or Enable and S1 to S4

8d

32bd

8d

8z, 4d, 6d, 6z

Automatically performed by amplifier Set set = actual

Activate the normal mode of operation; external and internal command signals are once again processed.

one from S1 to S4 and one from + or -

8z, 4d, 6d, 6z

4z, 2z

Signal at Input

0V

0V

24V

24V

S1 ∧ S2 ∧ S3 ∧ S4 = 0V

(S1 ∨ S2 ∨ S3 ∨ S4) = 24V

∧

(+ ∨ -) = 24V

Drive to starting position. The starting position corresponds to the active setpoints. The selected internal command signal (S1 ∨ S2 ∨ S3 ∨ S4), and possibly the external command signal is used.

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Series VRD350 and VRD355

The internal command signal used for this purpose serves as a final value

(position value). The drive is run to this value according to the pre-set ramp.

Status Chart of Safety Function

External Control, Pressure Control

Pressure sensors can be designed in two or three-wire technology. The sensor signal is either a voltage from 0...10V or a current from 0...20mA or 4...20mA. The parameter E11 should be set between 7 and 9. Apart from an adjustment to the sensor signal, this also prevents controller parameters U13 < 0 (see page 22). Wire break monitoring is only possible with 4...20mA sensor signals.

When connecting pressure sensors we recommend that great care be taken. The zero volt wiring, screening and PE connection are critical. Faults in the signal can lead to a triggering of the wire break monitor. Instabilities in the control loop are also possible.

The scaling of the sensor signal is very important for a high quality pressure control. This also guarantees a maximum exploitation of the resolution.

The maximum pressure to be controlled is decisive.

The closer the sensor signal is to 10V or 20mA, the more favourable this is. In other words, the measuring range of the sensor must be adapted to the pressure range of the application. Furthermore, the setting of the actual value adjustment must also be given special attention. At the maximum pressure to be controlled, almost 9.90V should appear in display U11.

Example:

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29

When setting the zero point, care must be taken because pressure valves do not permit a drop in pressure to 0 bar on account of their design.

Parker Hannifin GmbH & Co. KG

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Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

The controller structure is shown in the figure on page 17. Pressure control loops and their dynamics are essentially determined by the system capacities. A presetting in the works is impossible. The parameters should be determined individually for each application. Controller parameters can be calculated from the loop amplifications using the equations on page 22. Should these calculations prove impossible, the parameter values have to be determined in tests.

The remote loop control is activated with E2 = 2.

Then P21 and P22 have the following meanings:

P21 Positive threshold activates controller

P22 Negative threshold activates controller

Display

0.00...9.99V

0.00...9.99V

Avoid instability of the control loop during the experimentation. This may cause damage to the drive or machine.

If E2 = 2 and P21 and P22 = 0, the control can be directly activated with the “Reset ramp“ input. This permits a selective external activation and deactivation of the control.

If E2 = 2, actual value U11 is used directly as a comparative value. This is different from the “Standard comparator function”, where the control difference

U12 is decisive.

Proportional pressure valves can oscillate on account of the system. This behaviour may be significant in the control loop, particularly through system feedbacks. In certain circumstances, this may be counteracted by adjusting the dither parameter (P5,

P6). Variations to the dither frequency are generally the most effective.

Remote Loop Control

Initially, the amplifier is in open loop operating mode. The solenoid current is in direct proportion to the command signal, resulting e.g. in a certain pressure using pressure control valves. By changing the “reset ramp” input to high, e.g. by using an external PLC, the amplifier is armed to function as a loop controller.

The comparator monitors the actual value signal.

In the case of pressure controls, mainly using switching controllers, P21 is preferably used. If the actual value now exceeds this comparative value, the control switches on.

The Effects of the Time Delay P23 and P24: always be set = 0.00. Other values give no function.

P24 for a delay when switching in the control with a switching controller. The control is switched on after a time delay of the preset time.

The status is displayed with the LED “Reset

Ramp“.

Input

Reset

Ramp

0

1

1

P23 with remote loop controller must

Ratio of actual value/ switching threshold smaller 1 smaller 1 larger 1

Control loop ooen open closed

LED

RESET

RAMP off on flashing

The output of the integral part (P17) starts at the same time with the value

0. This is why negative oscillations may occur due to the system.

Even if the actual value is under the switching threshold, the control remains active. The signal at the „Ramp reset“ input is required to switch off the control. The control remains active until „Reset ramp“ returns to 0V.

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Digital Power Amplifier

Series VRD350 and VRD355

Setting E2 = 3 activates the bypass, P13 determines the gain of the bypass loop, P15 is without any function and P16 sets the P-portion, P17 the

I-Portion and P18 the D-Portion of the PID-controller.

Bypass Controller

See also block diagram on page 19.

The bypass controller is designed as a parallel circuit of a P-amplifier with an PID-controller. The processed command signal from U10 is hereby used directly as an input to the P-amplifier. Following calculation, the signal is added to the adjusting signal of the PID controller. This is supplied with the control deviation (U12).

This operating mode enables enhanced dynamic performance with simplified parameter setting.

3.13. Programmable Comparator Function

General Comparator Funktions

The function of the comparators and the comparative value result from the combinations shown in table below.

P21 and P22 can each be adjusted over the full range from 0...+9.99V. The setting resolution is

10mV. P21 is responsible for control deviations ≥ 0 and P22 for control deviations <0.

The window centre is defined by:

Set = Actual or [Set - Actual] = 0

The window itself by P21 and P22

The output delay P23 and P24 (time for switching output on and off) can be set in steps of 10ms with the maximum value of 9.96 sec. The opto-decoupled comparator output signal can be monitored at terminal 14b.

Comparator function with E2 = 1, 3 or 4

To implement the monitoring functions with:

• controlled machine functions, and with

• controls (position, speed and pressure controls, etc.)

Card design open loop/ closed loop open loop open loop closed loop closed loop closed loop closed loop closed loop closed loop open loop closed loop

Setting

E2

0

0

0

0

0

1, 3, 4

1, 3, 4

2

2 only 0

1, 2, 3, 4

Enable

0V

24V

24V

24V

24V

24V

24V

24V

24V

24V

24V

Setting

P21/P22 random

≠ 0,00

≠ 0,00

≠ 0,00

≠ 0,00

≠ 0,00

≠ 0,00

≠ 0,00

≠ 0,00

=0,00

=0,00

Comparative value in window random

U2 outside

U2 inside

U12 outside

U12 inside

U12 outside

U12 inside

U11 outside

U11 inside random random

Comparator output

0V

0V

24V

0V

24V

0V

24V

0V

24V

0V

0V

LED RESET RAMP

Input Input off on off flashes off flashes on flashes fast on flashes fast off flashes on flashes fast see page 29 see page 29 off off on on

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The comparator used to generate a COMMAND

SIGNAL REACHED (“IN POSITION“) signal.

Simple (actual value) checks can thus be performed

(e.g. clamping pressure monitoring). The control difference U12 is compared with the defined window in the comparator. The comparator signal is output accordingly depending on the result of the comparison.

A set comparator (within the window) is indicated by a slowly flashing LED “RESET RAMP”. If the

“Reset Ramp” signal is also present, the LED flashes quickly.

Connection to the PC is via a so-called null modem cable.

The program PROVRD350/355 (Order No. HR

59.500 010) is available to carry out programming and remote control. This permits simple remote control and programming of the amplifier cards via a PC. On one hand this facilitates programming and increases the clarity, and on the other it opens up the possibility of a convenient storage and documentation of parameter configurations.

The program can also be used to adapt the basic settings (default settings) (see also page 14) to the user’s specific circumstances.

Comparator Function with E2 = 2

The comparator is used to generate a switching threshold for the control. The actual value U11 is compared directly with the values defined in P21 and P22. If U11 exceeds the comparative value, the control is switched on. One condition, however, is that a signal is also present at the “Reset

Ramp“ input.

3.14. Serial Interface

Remote operation or remote setting of parameters can be carried out by means of the serial interface. The following transmission parameters are applicable:

Transmission rate 9600 Baud

Data format

Voltage level

8 data-bits, 1 stop-bit, parity none

5V

Assignment of the Serial Interface

Parameter changes via the serial interface should only be carried out by trained personnel. The drive must be stopped during parameter changes. We recommend switching the card’s enable off.

Only the PROVRD versions V4.0 and later may be used for amplifier cards with software release V2.0 and later.

PROVRD version V4.0 can be used with older software versions (as of V1.04) of the amplifier cards.

3.15. ABG35S

The plug-in control panel ABG35S can easily be attached to amplifier cards of the VRD355 range for displaying and changing parameters and values.

Afterwards, it can be removed, thus disabling unauthorized access to the cards. It provides the same keys and 7-segment display as the front panel of the VRD350. Further, the same test sockets are incorporated for commissioning and servicing.

As an additional feature, the ABG35S enables the storage of one complete parameter set on-board.

By this means, the settings can be copied from one amplifier to an unlimited number of others in a very short time. No further components are required

(see also page 23).

The data record in the ABG35S must correspond to the software version of the amplifier.

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32 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

4. Operating and Error Messages

Supply

The LED „24V“ lights up when the supply voltage is present.

4.1. Enable

• After the enable signal has been applied to terminal 8d, the LED "ENABLE" flashes for the period of the time delay set in parameter E9.

• Once the time delay elapses, the flashing signal becomes a continuous signal and the output stages are enabled.

• The enable input is electrically isolated by means of an opto-coupler.

• If no electrical isolation is required, terminal 2d must be bridged with terminal 26d and terminal

32z must be bridged with terminal 32bd of the unit by the customer.

Warning >>10V

The following conditions apply for this LED:

E2 Enable conditions

0 Sum S1 to S4 and SW5 and

SW6 <  9.95

 V

0 Sum S1 to S4 and SW5 and

SW6 >  9.95

 V

1...4

U12 <  9.95

 V

1...4

U12 >  9.95

 V

LED >>10V off on off on

4.2. RESET RAMP

A 24V signal at the Reset Ramp input (terminal

18z) immediately sets the ramp function generator to zero. Once the signal is switched off, the ramp function generator starts again from zero. The preset time constant (S5 to S8) is then used to run up the preset command signal. The Reset Ramp input is galvanically isolated via opto-couplers (see figure page 9).

4.3. Malfunction and Error Messages

• The current in the output stages is monitored in the amplifier. If the total current exceeds a specific limit, an electronic cut-out responds and switches the output stages off. At the same time, the signal at the ‘Error’ output (terminal 14d) is set to 0V (cable fracture detection).

• Malfunction signals are not cleared by switching off the supply voltage, but by removing the enable signal. Otherwise error diagnosis on the basis of error messages is no longer possible.

• The fault output is electrically isolated by an opto-coupler and short circuit protected by a

PTC resistor

• If no electrical isolation is required, terminal

32z must be bridged with terminal 32bd by the customer.

Possible Error Messages

Display Fault

--1 Programming error E2

--2

--3

Transducer cable fracture (only if E12 = 1)

Excess current cut-out active

--4

--5

--6

A/D-converter failure

Cable fracture detection not possible

Error is canceled by releasing arrow keys

No valid data in ABG35S or incorrect

--7

--8 software version

Read error when reading ABG35S

Write/read error (verify)

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33 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

4.4. Comparator Output

• When the switching conditions for the comparator are fulfilled, the signal at the output

Comparator (terminal 14b) is set to 24V.

• The ‘comparator’ output is opto-decoupled (see also page 9) and is short circuit protected by a

PTC resistor.

• The LED “reset ramp“ is also used for display of the comparator status (see also page 31).

4.5. Externally selected Command Signals and

Directions

4 LEDs indicate the selected command signal

(S1 to S4). 2 LEDs indicate the selected direction

(+ or -).

The LED’s + and - are also used to show the signs for internal measured values and parameters (see also page 20).

Select

Direction none

+

-

Sign for meas. value parameter positive negative positive negative positive negative

LED for Direction

+ flashes off flashes fast on flashes off off flashes off flashes on flashes fast

24

26

28

30

32

16

18

20

22

8

10

12

14

Pin

2

4

6

5. Terminals on Rear Connector d

0V external

S2

S3

Enable

Feedback input

Command signal 6U

E+

Error

Command signal 6U

E-

PE

-10V output

Solenoid A

Solenoid B

Supply 0V

Solenoid A

Solenoid B

Supply +24V b not connected not connected not connected not connected

Feedback value display

RS232C TXD

Comparator

PE (decoupled)

PE

PE (decoupled)

Solenoid A

Solenoid B

Supply 0V

Solenoid A

Solenoid B

Supply +24V z

- direction (A)

+ direction (B)

S4

S1

RS232C RXD

Command signal 5 not connected not connected

Reset Ramp

+10V output

Solenoid A

Solenoid B

Analogue 0

Solenoid A

Solenoid B

24V external

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34 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

6. Parameter List

Parameter Description

S1 - S4 Command signals as voltage

S5 - S8 Ramp time in seconds

H1, H2 Command signal simulation (set value as voltage)

P1

P2

Offset

Linearisation (not active / active)

P3

P4

P5

Gain factor for solenoid A

Gain factor for solenoid B

P6

P7

Dither amplitude

Dither frequency

Step function for solenoid A

Step function for solenoid B P8

P9, P10 Initial current for solenoid A and B (0,8A / 2,7A / 3,5A)

P11 Command signal (not invertied / inverted)

P12

P13

P14

P15

P16

P17

P18

Feedback value (not invertied / inverted)

P-portion (K

P,1

) for control deviation ≤ threshold P15

(or bypass with E2 = 3)

T-portion of PT-element

Threshold for switch over to K

P-portion (K

P,2

P,2

(0...10V)

) for control deviation > threshold P15

I-portion

D-portion

P19

P20

T-portion of DT

1

-element

Gain for feedback signal

P21

P22

P23

P24

E1

E2

E3

E4

E5

E6

E7

E8

E9

E10

E11

E12

E13

E14

E15

E16

Window [Set-feedback] < 0

Window [Set-feedback] > 0

Time delay (into window)

Time delay (out of window)

Reserved

Operating mode (only with feedback option)

Open- /closed loop (internal/external, bypass, safety function)

Solenoid type

P-portion current control, control deviation > 0 (energ.)

I-portion current control, control deviation > 0 (energ.)

P-portion current control, control deviation < 0 (deenerg.)

I-portion current control, control deviation < 0 (deenerg.)

Ramp change (constant rise rate / constant time base

- only for internal set values S1-S4))

Time delay for enable signal (0...10s)

Reserved

Type of feedback transducer (only when feedback option is selected in)

Cable fracture detection (only when feedback option is selected in (active / not active))

Serial Interface (active / not active)

Factor for P13 and P16 (only when feedb.op.is sel.)

Select load / store (only accessible for VRD355)

Activates load/store E15 (only with VRD355)

-

-

-

-

-

0 / 1...4

1...7

0...255

0...255

0...255

0...255

1 / 0

0...255

0.00...9.99

0...255

0...255

0...255

0...255

0.00...2.00

0.00...9.99

0.00...9.99

0.00...9.96

0.00...9.96

0 / 1

-

-

-

-

-

-

-

-

-

-

V

V s s

-

-

-

V

V s

-

-

V

Hz

A

-

-

Unit Display

V 0...9.99

s

V

V

-

0...39.5

± 0...9.99

0...+2.99 / 0...-2.99

0 / 1...5

0.00...2.00

0.00...2.00

0.00...3.03

0...647 (in steps)

0.00...0.81/ 2.7 / 3.5

A 0.00...0.81/ 2.7 / 3.5

mA -205...+183, -704...+630, -917...+821

-

1 / -1

1 / -1

0...255

0.00...9.99

0...255

1...10

1 / 0

1 / 0

0...16

L... / S...

...S or ...L (run)

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35 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Parameter

S1 - S4 0

Factory Setting, Basic Version VRD35X - 031 - 00

S5 - S8 0

H1, H2 Set to 0 after commissioning

P1 0.00

P2

P3

P4

P5

P6

0

1.00

1.00

P15

0.80

110Hz

P7

P8

0.00

0.00

P9, P10 0.00

P11

P12

P13

P14

1

1

0

0

9.99

P16

P17

P18

P19

P20

0

10

0

0

P21

P22

P23

1.00

0.00

0.00

0.00

0.00

P24

E1

E2

E3

E4

0

0

3

110

90 E5

E6

E7

110

95

1 E8

E9

E10

E11

E12

0.00

185

6

0

1 E13

E14

E15

E16

-

-

0

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36

Digital Power Amplifier

Series VRD350 and VRD355 old new

Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional DC valves, open loop version

IA VRD UK.INDD RH 02.06

37 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional DC valves with spool position feedback

IA VRD UK.INDD RH 02.06

38 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional pressure control valves, open loop version

IA VRD UK.INDD RH 02.06

39 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional pressure control valves, closed loop version

IA VRD UK.INDD RH 02.06

40 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional flow control valves, open loop version

IA VRD UK.INDD RH 02.06

41 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional flow control valves, closed loop version

IA VRD UK.INDD RH 02.06

42 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

Wiring diagram for proportional DC valves, external closed loop

IA VRD UK.INDD RH 02.06

43 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division

Installation Manual

Digital Power Amplifier

Series VRD350 and VRD355

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44 Parker Hannifin GmbH & Co. KG

Hydraulic Controls Division