W.E.St. Elektronik PAM-195-P-PVG Technical Documentation Manual

Technical Documentation

PAM-195-P-PVG

Power amplifier for directional valves with ratiometric input

CONTENTS

1 General Information ...................................................................................................................................................... 3

1.1 Order Number ....................................................................................................................................................... 3

1.2 Scope of supply .................................................................................................................................................... 3

1.3 Accessories .......................................................................................................................................................... 3

1.4 Symbols used ....................................................................................................................................................... 4

1.5 Legal notice ................................ ................................................................ .......................................................... 4

1.6 Safety instructions ................................................................................................................................................ 5

2 Characteristics .............................................................................................................................................................. 6

2.1 Device description ................................................................................................................................................ 7

3 Use and application ...................................................................................................................................................... 8

3.1 Installation instruction ........................................................................................................................................... 8

3.2 Commissioning ..................................................................................................................................................... 9

4 Function modes and technical description .................................................................................................................. 10

4.1 LED Indications .................................................................................................................................................. 10

4.2 Typical system structure ..................................................................................................................................... 11

4.3 Method of operation ............................................................................................................................................ 11

4.4 Input and output signals ..................................................................................................................................... 12

4.5 Circuit diagram ................................................................................................................................................... 13

4.6 Typical wiring ...................................................................................................................................................... 14

4.7 Input connection (examples)............................................................................................................................... 14

4.8 Technical data .................................................................................................................................................... 15

5 Parameter ................................................................................................................................................................... 16

5.1 Parameter list ..................................................................................................................................................... 16

5.2 Basic parameters ................................................................................................................................................ 17

5.2.1 LG (Changing the language for the help texts) .......................................................................................... 17

5.2.2 MODE (Switching between parameter groups) .......................................................................................... 17

5.2.3 SENS (Failure monitoring) ......................................................................................................................... 17

5.2.4 CCMODE (Activation of the characteristic linearization) ............................................................................ 18

5.3 Input signal adaption .......................................................................................................................................... 18

5.3.1 LIM (Signal monitoring) .............................................................................................................................. 18

5.3.2 RA (Ramp function) ................................................................................................................................... 19

5.4 Output signal adaption ........................................................................................................................................ 20

5.4.1 CC (Characteristics linearization) .............................................................................................................. 20

5.4.2 MIN (Overlap compensation) ................................ ..................................................................................... 21

5.4.3 MAX (Output scaling) ................................................................................................................................. 21

5.4.4 TRIGGER (Threshold value of MIN function) ............................................................................................. 21

5.4.5 SIGNAL:U (Output polarity) ....................................................................................................................... 22

5.5 Parameters of the power stage................................................................................................ ........................... 22

5.5.1 CURRENT (Nominal output current) .......................................................................................................... 22

5.5.2 DAMPL (Dither amplitude) ......................................................................................................................... 22

5.5.3 DFREQ (Dither frequency) ......................................................................................................................... 22

5.5.4 PWM (PWM frequency) ............................................................................................................................. 23

5.5.5 ACC (Auto adaptation of the closed loop current controller) ...................................................................... 23

5.5.6 PPWM (Solenoid current controller P gain) ............................................................................................... 24

5.5.7 IPWM (Solenoid current controller I gain) .................................................................................................. 24

5.6 Process data (Monitoring) .................................................................................................................................. 24

6 Appendix .................................................................................................................................................................... 25

6.1 Failure monitoring ............................................................................................................................................... 25

6.2 Troubleshooting .................................................................................................................................................. 25

6.3 Description of the command structure ................................................................................................................ 26

7 Notes .......................................................................................................................................................................... 27

Page 2 of 27 PAM-195-P-PVG 18.06.2019

1

1 General Information

1.1 Order Number

PAM-195-P-PVG-22301 - power amplifier for directional valves with integrated power limitation function

1.2 Scope of supply

The scope of supply includes the module plus the terminal blocks which are a part of the housing.
The Profibus plug, interface cables and further parts which may be required should be ordered separately.
This documentation can be downloaded as a PDF file from www.w-e-st.de.

1.3 Accessories

WPC-300 - Start-Up-Tool (downloadable from our homepage – products/software)

The number of the version consists of the hardware-version (first two digits) and the software-version (second two digits).
Because of the development of the products these numbers can vary. They are not strictly necessary for the order. We will
always deliver the newest version.

Page 3 of 27 PAM-195-P-PVG 18.06.2019

1.4 Symbols used

General information

Safety-related information

1.5 Legal notice

W.E.St.

Gewerbering 31
D-41372 Niederkrüchten

Tel.: [phone]
Fax.: [phone]

Homepage: www.w-e-st.de or www.west-electronics.com
EMAIL: [e-mail]

Date: 18.06.2019

The data and characteristics described herein serve only to describe the product. The user is required to
evaluate this data and to check suitability for the particular application. General suitability cannot be inferred
from this document. We reserve the right to make technical modifications due to further development of the
product described in this manual. The technical information and dimensions are non-binding. No claims may
be made based on them.

This document is protected by copyright.

Elektronik GmbH

Page 4 of 27 PAM-195-P-PVG 18.06.2019

1.6 Safety instructions

Please read this document and the safety instructions carefully. This document will help to define the product
area of application and to put it into operation. Additional documents (WPC-300 for the start-up software) and
knowledge of the application should be taken into account or be available.
General regulations and laws (depending on the country: e.g. accident prevention and environmental protec­tion) must be complied with.

These modules are designed for hydraulic applications in open or closed loop control circuits.
Uncontrolled movements can be caused by device defects (in the hydraulic module or the
components), application errors and electrical faults. Work on the drive or the electronics must
only be carried out whilst the equipment is switched off and not under pressure.

This handbook describes the functions and the electrical connections for this electronic as­sembly. All technical documents which pertain to the system must be complied with when
commissioning.

This device may only be connected and put into operation by trained specialist staff. The in­struction manual must be read with care. The installation instructions and the commissioning
instructions must be followed. Guarantee and liability claims are invalid if the instructions are
not complied with and/or in case of incorrect installation or inappropriate use.

CAUTION!

All electronic modules are manufactured to a high quality. Malfunctions due to the failure of
components cannot, however, be excluded. Despite extensive testing the same also applies
for the software. If these devices are deployed in safety-relevant applications, suitable external
measures must be taken to guarantee the necessary safety. The same applies for faults which
affect safety. No liability can be assumed for possible damage.

Further instructions

 The module may only be operated in compliance with the national EMC regulations. It is

the user’s responsibility to adhere to these regulations.

 The device is only intended for use in the commercial sector.

 When not in use the module must be protected from the effects of the weather, contamina-

tion and mechanical damage.

 The module may not be used in an explosive environment.

 To ensure adequate cooling the ventilation slots must not be covered.

 The device must be disposed of in accordance with national statutory provisions.

Page 5 of 27 PAM-195-P-PVG 18.06.2019

2 Characteristics

This module is used for the control of a directional valve with two solenoids. Various adjustable parameters
allow an optimized adaptation to the respective valve. The integrated power amplifier with a short cycle time of
0,125 ms for the current loop is an inexpensive and space-saving solution.

Setpoint setting is realized via a ratiometric input. That means the command signal is provided as precentral
value relating to the supply voltage. For that the relevant voltage is measured at a separate input. Via another
input the command value is set by a signal between 25% and 75% of the supply voltage with 50% as zero po­sition.

The output current is closed loop controlled and therefore independent from the power supply and the solenoid
resistance. The output stage is monitored for cable breakdown, is short circuit proof and disables the power
stage in case of an error.

RAMP, MIN and MAX, the DITHER (frequency and amplitude) and the PWM frequency are programmable.
In addition, the valve characteristics can be linearized via 10 XY-points. For example: using pressure valves a

linear behavior between input signal and pressure can be reached.

Typical applications: Control with ratiometric joysticks (Danfoss compatible control).

Features

 Control of directional valves
 Compact housing
 Digital reproducible adjustments
 Ratiometric command value input
 Separate reference input for the ratiometric command input
 Characteristics linearization via 10 XY-points per direction
 Free parameterization of RAMPS, MIN und MAX, output current, DITHER (frequency, amplitude)
 Nominal output current range: 0,5… 2,6 A
 Simple and application orientated parameter settings via WPC-software
 Failure monitoring and extended function check

Page 6 of 27 PAM-195-P-PVG 18.06.2019

V:

ID:

Add.:Date:

Made in Germany

W.E.ST.

Ready

1 2 3 4

5 6 7 8

9 10 11 12

14 15 1613

D-41372 Niederkrüchten
Homepage: http://www.w-e-st.de

W.E. ST.

Elektronik

131415

9

10

11

12

16

A B

Klemmblöcke (steckbar)
Terminals (removable)

LEDs

USB
interface

Typenschild und Anschlussbelegung
Type plate and terminal pin assignment

23,0000 mm99,0000 mm

114,0000 mm

2.1 Device description

Page 7 of 27 PAM-195-P-PVG 18.06.2019

3 Use and application

3.1 Installation instruction

 This module is designed for installation in a shielded EMC housing (control cabinet). All cables which

lead outside must be screened; complete screening is required. It is also a requirement that no strong
electro-magnetic interference sources are installed nearby when using our open and closed loop con­trol modules.

 Typical installation location: 24V control signal area (close to PLC)

The devices must be arranged in the control cabinet so that the power section and the signal section
are separate from each other.
Experience shows that the installation space close to the PLC (24 V area) is most suitable. All digital
and analogue inputs and outputs are fitted with filters and surge protection in the device.

 The module should be installed and wired in accordance with the documentation bearing in mind EMC

principles. If other consumers are operated with the same power supply, a star-connected ground wir­ing scheme is recommended. The following points must be observed when wiring:

 The signal cables must be laid separately from power cables.
 Analogue signal cables must be screened.
 All other cables must be screened if there are powerful interference sources (frequency

converters, power contactors) and cable lengths > 3m. Inexpensive SMD ferrites can be
used with high-frequency radiation.

 The screening should be connected to PE (PE terminal) as close to the module as possi-

ble. The local requirements for screening must be taken into account in all cases. The
screening should be connected to at both ends. Equipotential bonding must be provided
where there are differences between the connected electrical components.

 With longer lengths of cable (>10 m) the diameters and screening measures should be

checked by specialists (e.g. for possible interference, noise sources and voltage drop).
Particular care is required with cables of over 40 m in length – the manufacturer should be
consulted if necessary.

 A low-resistance connection between PE and the mounting rail should be provided. Transient interfer-

ence is transmitted from the module directly to the mounting rail and from there to the local earth.

 Power should be supplied by a regulated power supply unit (typically a PELV system complying with

IEC364-4-4, secure low voltage). The low internal resistance of regulated power supplies gives better
interference voltage dissipation, which improves the signal quality of high-resolution sensors in partic­ular. Switched inductances (relays and valve coils connected to the same power supply) must always
be provided with appropriate overvoltage protection directly at the coil.

Page 8 of 27 PAM-195-P-PVG 18.06.2019

Step

Task

Installation

Install the device in accordance with the circuit diagram. Ensure it is wired correctly
and that the signals are well shielded. The device must be installed in a protective
housing (control cabinet or similar).

Switching on for the first
time

Ensure that no unwanted movement is possible in the drive (e.g. switch off the
hydraulics). Connect an ammeter and check the current consumed by the device. If
it is higher than specified, there is an error in the wiring. Switch the device off imme­diately and check the wiring.

Setting up communication

Once the power input is correct the PC (notebook) should be connected to the
serial interface. Please see the WPC-300 program documentation for how to set up
communication.

ATTENTION! A USB driver has to be installed and properly configured.
See WPC-300 short guideline.

Further commissioning and diagnosis are supported by the operating software.
ATTENTION! The COMPORT (in WPC-300) has to be closed before the USB plug

is to be disconnected. Otherwise the WPC-300 is going to be instable.

Pre-parameterization

Now set up the following parameters (with reference to the system design and circuit
diagrams):

The nominal output CURRENT and the typical valve parameters such as DITHER
and MIN/MAX.

Pre-parameterization is necessary to minimize the risk of uncontrolled movements.

Control signal

Check the control signal with an amp meter. The control signal (the current of the
solenoid) is within the range of 0... 2, 6A. In the actual status it should show approxi­mately 0 A.
ATTENTION! You can monitor the current of the solenoids also in the WPC-300 pro­gram.

Switching on the hydrau­lics

The hydraulics can now be switched on. The module is not yet generating a signal.
Drives should be at a standstill or drift slightly (leave its position at a slow speed) if it
is a proportional valve.

Activating ENABLE

CAUTION! The drive can now leave its position and move to an end position with full
speed or the pressure can reach maximum. Take safety measures to prevent per­sonal injury and damage.

The amplifier can be controlled now via the command value input.

3.2 Commissioning

Page 9 of 27 PAM-195-P-PVG 18.06.2019

LEDs

Description of the LED function

GREEN + YELLOW

1. Chasing light (over all LEDs): The bootloader is active. No normal functions
are possible.

2. All LEDs flash shortly every 6 s: An internal data error was detected and cor­rected automatically! The module still works regularly. To acknowledge the error
the module has to be cycle powered.

YELLOW + YELLOW

Both yellow LEDs flash oppositely every 1 s: The nonvolatile stored parameters
are inconsistent! To acknowledge the error the data have to be saved with the SAVE
command or the corresponding button in the WPC. If the function of the module has
changed via the FUNCTION parameter, all parameters are deleted purposely and set
to default values. In this case the LEDs indicate no error, but a desired state. To
acknowledge please save.

GREEN

Identical to the READY output.

OFF: No power supply or ENABLE is not activated
ON: System is ready for operation

Flashing: Error detected (e. g. valve solenoid or 4… 20 mA).

Not active when SENS = OFF.

YELLOW

LED in the middle position = Current to the solenoid; the intensity is proportional to

the actual output current.

4 Function modes and technical description

4.1 LED Indications

Page 10 of 27 PAM-195-P-PVG 18.06.2019

4.2 Typical system structure

This minimal system consists of the following components:

(*1) proportional valve
(*2) hydraulic cylinder
(*3) power amplifier PAM-195-P-PVG
(*4) reference supply and ratiometric signal

4.3 Method of operation

This power amplifier is controlled by a ratiometric input signal (normally from a joystick). That means 25% up
to 75% of the separately measured voltage value are used as command signal. 50% are the zero position. An
ENABLE signal (typically 24V) activates the module and the READY output indicates this, if no internal or ex­ternal error was detected.

The integrated standard functions will be configured via different parameters.
In case of a fault, the power output stage will be deactivated and the fault will be indicated through a deac-

tivated READY output and a flashing READY LED.
The output current is closed loop controlled whereby a high accuracy and a good dynamic will be obtained. All

custom proportional valves (up to 2,6A) may be controlled with this power amplifier.

Page 11 of 27 PAM-195-P-PVG 18.06.2019

Connection

Supply

PIN 7

Power supply (see technical data)

PIN 8

0 V (GND) Power supply (ground).
Attention, PIN 8 and PIN 11 are connected internally. PIN 11 is used as the GND potential
for the command and feedback signals.

Connection

Reference voltages output

PIN 12

Reference output voltage (8 V).

Connection

PWM output

PIN 3 / 4

Current controlled PWM outputs for solenoid A.

PIN 1 / 2

Current controlled PWM outputs for solenoid B.

Connection

Analogue input signals

PIN 9

Command signal input, range 25…75 % of reference value (supply voltage).

PIN 14

Reference value, supply voltage of the setpoint device (8… 30 V).

PIN 10 / 13

Potential connectors of the inputs, have to be connected to 0 V (GND)

PIN 11

0 V (GND) reference, e.g. for the signal inputs.

Connection

Digital inputs and outputs

PIN 15

Enable Input:
This digital input signal initializes the application.

The output and the READY signal will be activated.
By deactivating error signals are reset.

PIN 5

READY output:
ON: Module is ready, no errors are detected
OFF: ENABLE (PIN 15) is deactivated or an error is detected.

4.4 Input and output signals

Page 12 of 27 PAM-195-P-PVG 18.06.2019

Ub cmd

24 V

Input Scaling

PE via DIN-RAIL

3

4

1

5

15

Ready

Enable

24 V output

USB Type B

PAM-195-P-PVG

9

14

0 V

25%..75%

10

13

Reference supply

voltage

ref. supply

Output Adaptation

24 V input

u

Power supply

7

8

0 V

Control program

RAMP Generator

Commands:

- AA:1 ... AA:4

Input Scaling

8... 30V

0 V

Command value

Linearisation

Commands:

- CCMODE

- CC

Commands:

- MIN:A and :B

- MAX:A and :B

- TRIGGER

- SIGNAL:U

DC

DC

24 V

0 V

PELV

C

Commands:

- LG (Language)

- MODE (Expert or Standard)

- SENS (Malfunction monitoring)

Power Stage

Commands:

- CURRENT

- DITHER

- PWM

- PPWM

- IPWM

ia

ib

2

solenoid-A

solenoid-B

e.g. for HAWE valves

3

4

1

2

solenoid-A

solenoid-B

wr

12

Reference voltage out

11

0 V

0 V

w

rv+

Commands:

- LIM

Serial

57600 Baud

8N1

USB

wa

4.5 Circuit diagram

Page 13 of 27 PAM-195-P-PVG 18.06.2019

Potentiometer / Joystick

GND PIN 11

Signal in PIN 9
0V PIN 10

PIN 14

Supply voltage

Enable

8765

16151413

1211109

Ratiometrischer Sollwert /
ratiometric command signal

Magnet A /
Solenoid A

4321

0V

Schirm /

Screen

PE

Spannungsversorgung /
Power Supply

0V

12 V / 24 V

Magnet B /
Solenoid B

+

V ref.

PE

Ready

Versorgung Sollwertgeber /
Supply of setpoint device

+

0V

0V

4.6 Typical wiring

4.7 Input connection (examples)

Page 14 of 27 PAM-195-P-PVG 18.06.2019

Power supply (Ub)
Power consumption max.

External fuse

[VDC]

[W]

[A]

12… 30 (incl. ripple)
60 (depending on type of solenoid, two solenoids

are active)
3 medium time lag

Reference voltage

[V]

8 ( maximum 25 mA)

Digital inputs

Input resistance

[V]
[V]

[kΩ]

OFF: < 2
ON : > 10
25

Digital outputs

Maximum current

[V]
[V]

[mA]

OFF: < 2
ON: max. Ub
50

Reference supply voltage
Ratiometric input

[V]

[%]

8… 30; min. 90 kOhm
25… 75; relating to reference value

Nominal PWM output current

PWM frequency

[mA]

[Hz]

500… 2600; broken wire monitored and short
circuit proof.

61...2604; adjustable in steps

Sample time (process control)
Sample time (solenoid current control)

[ms]
[ms]

1
0,125

Interface

USB type B
Virtual COM port driver (WPC-300):
9600… 57600 Baud (Default = 57600),
1 Stoppbit, No parity, No handshake

Housing

Snap-On Module EN 50022
Polyamide PA 6.6
Combustibility class V0 (UL94)

Weight

[kg]

0,190

Protection class
Temperature range
Storage temperature
Humidity
Vibration

[°C]
[°C]

[%]

-

IP20

-20… 60

-20 …70
<95 (not condensing)
IEC 60068-2-6 (category C)

Connections

USB type B
4 x 4pol. screw terminals
PE: direct via DIN rail

EMC

EN 61000-6-2: 8/2005
EN 61000-6-4: 6/2007 ; A1:2011

4.8 Technical data

Page 15 of 27 PAM-195-P-PVG 18.06.2019

Group

Command

Default

Unit

Description

Basic parameters

LG

EN

-

Changing language help texts

MODE

STD

-

Parameter view

SENS

AUTO

-

Malfunction monitor

CCMODE

OFF

-

Activation and deactivation of the characteristic linearization

Input signal adaptation

Signal monitoring

LIM

1000

0.01 %

Range for the input signal monitoring

Ramp function

RA:1

RA:2

RA:3

RA:4

100

100

100

100

ms

ms

ms

ms

Command signal four quadrant ramp times

Output signal adaptation

CC

-

X Y

Free definable characteristic linearization

MIN:A

MIN:B

0

0

0.01 %

0.01 %

Deadband compensation

MAX:A

MAX:B

10000

10000

0.01 %

0.01 %

Output scaling

TRIGGER

200

0.01 %

Deadband compensation trigger point

SIGNAL:U

+

-

Output polarity

Parameters of the power stage

CURRENT

1000

mA

Rated solenoid current

DAMPL

500

0.01 %

Dither amplitude

DFREQ

121

Hz

Dither frequency

PWM

2604

Hz

PWM frequency

ACC

ON

-

Current loop auto adjustment

PPWM

IPWM

7

40

-

-

P-Gain of the current loop
I-Gain of the current loop

5 Parameter

5.1 Parameter list

Page 16 of 27 PAM-195-P-PVG 18.06.2019

Command

Parameters

Unit

Group

LG X

x= DE|EN

-

STD

Command

Parameters

Unit

Group

MODE X

x= STD|EXP

-

STD

Command

Parameters

Unit

Group

SENS X

x= ON|OFF|AUTO

-

STD

5.2 Basic parameters

5.2.1 LG (Changing the language for the help texts)

Either German or English can be selected for the help texts in the WPC-300 program.

CAUTION: After changing the language settings the parameter list has to be updated by pressing the
speed button “ID”.

5.2.2 MODE (Switching between parameter groups)

This command changes the parameter mode. Various commands (defined via STD/EXP) are blanked out in
standard mode. The several commands in expert mode have more significant influence on the system perfor­mance. Therefore they should be changed with care.

5.2.3 SENS (Failure monitoring)

This command is used to activate/deactivate the monitoring functions (4… 20 mA sensors, output current, sig-

nal range and internal failures) of the module.
ON: All monitoring functions are active. Detected failures can be reset by deactivating the ENABLE input.

This mode should be used in case of active enabling and monitoring by a PLC (READY signal).
OFF: No monitoring function is active.
AUTO: Auto reset mode. All monitoring functions are active. If the failure does not exist anymore, the mod-

ule automatically resumes to work.

Page 17 of 27 PAM-195-P-PVG 18.06.2019

Normally the monitoring functions are always active because otherwise no errors are detectable via
the READY output. Deactivating is possible especially for troubleshooting.

AUTO MODE: The module checks each second the actual failure status, which will (in case of a per­sistent error) trigger the LED and the READY output for a short time.

Command

Parameters

Unit

Group

CCMODE X

x= ON|OFF

-

EXP

Command

Parameters

Unit

Group

LIM X

x= 0… 2000

0.01 %

STD

0%

Working range

Error range

10%

25%

75%

90%

100%

5.2.4 CCMODE (Activation of the characteristic linearization)

This command will be used for activation or deactivation of the characteristics linearization (CC, CCA and
CCB). Through deactivating this parameter a simple and quick estimation of the linearization is possible.

CAUTION: If CC command is used, parameters MIN, MAX and TRIGGER have to be considered.

CC and those commands affect each other. Pay attention to that if it is necessary to use both kind
of settings at the same time.

5.3 Input signal adaption

5.3.1 LIM (Signal monitoring)

The signal monitoring deactivates the output current and the READY output if the input signal leaves the per­mitted range after scaling. This function makes it possible to detect a short circuit or cable break of a joystick
or potentiometer.

Example: LIM 1000 (10 % upper and lower
limit, is also default).

The percentage values refer to the ratiometric sig­nal. If the input signal increases above 90% or de­creases below 10% it will be detected as error.

Page 18 of 27 PAM-195-P-PVG 18.06.2019

Command

Parameters

Unit

Group

RA:I X

i= 1… 4

x= 1… 120000

-

ms

STD

t

Ausgang/Output A

Ausgang/Output B

RA:1

RA:2

RA:3 RA:4

5.3.2 RA (Ramp function)

Four quadrants ramp function.
The first quadrant means the acceleration ramp for solenoid A and the second one stands for the deceleration

ramp of solenoid A. According to this the third quadrant represents the acceleration ramp for solenoid B so
that the fourth quadrant remains for the deceleration ramp for solenoid B.

ATTENTION: Because of internal calculations rounding errors may be occur on the display.

Page 19 of 27 PAM-195-P-PVG 18.06.2019

Command

Parameters

Unit

Group

CC:I X Y

i= -10… 10

x= -10000… 10000

y= -10000… 10000

-

0.01%

0.01%

CCMODE=ON

5.4 Output signal adaption

5.4.1 CC (Characteristics linearization)

A user defined signal characteristic can be set by this function. For activating the parameter CCMODE has to
be switched to ON.

The positive indexes stand for the solenoid A, the negative ones represent the solenoid B. The curve is calcu­lated according to the equation of the linear interpolation: y=(x-x1)*(y1-y0)/(x1-x0)+y1.

The influence of the linearization can be estimated via the process data on the monitor or on the oscilloscope.

For the input of the characteristics linearization, the WPC-300 program provides a table and a graphic data
input. The input signal is mapped on to the X-axis and the output signal is mapped on to the Y-axis.

Page 20 of 27 PAM-195-P-PVG 18.06.2019

Command

Parameters

Unit

Group

MIN:I X

MAX:I X

TRIGGER X

i= A|B

x= 0… 6000

x= 5000… 10000

x= 0… 3000

-

0.01%

0.01%

0.01%

STD

2

MAX:A

MIN:A

MIN:B

MAX:B

Input

Output

TRIGGER

5.4.2 MIN (Overlap compensation)

5.4.3 MAX (Output scaling)

5.4.4 TRIGGER (Threshold value of MIN function)

The output signal is adapted to the valve by these commands. With the MAX value the output signal (the maxi­mum valve current) will be defined. With the MIN value the overlap (dead band of the valve) will be compen­sated. Via the TRIGGER the activation point of the MIN function is set and so a non-sensitive range around
the zero-point2 can be specified.

CAUTION: If the MIN value is set too high, it influences the minimal velocity, which cannot be
adjusted any longer.

This dead band is necessary, in order to avoid unrequested activations caused by small variations of the input signal. If

this module is used in a position controls, the TRIGGER value should be reduced (typical: 1…10).

Page 21 of 27 PAM-195-P-PVG 18.06.2019

Command

Parameters

Unit

Group

SIGNAL:U X

x= + | -

-

STD

Command

Parameters

Unit

Group

CURRENT X

x= 500… 2600

mA

STD

Command

Parameters

Unit

Group

DAMPL X

DFREQ X

x= 0… 3000

x= 60… 400

0.01 %

Hz

STD

3

5.4.5 SIGNAL:U (Output polarity)

This command allows switching the direction of the output signal (A/B).

5.5 Parameters of the power stage

5.5.1 CURRENT (Nominal output current)

The nominal solenoid current is set with this parameter. The DITHER and also the MIN/MAX parameter al­ways refer to the selected current range.

5.5.2 DAMPL (Dither amplitude)

5.5.3 DFREQ (Dither frequency)

The dither3 can be defined freely with this command. Different amplitudes or frequencies may be required de­pending on the respective valve. The dither amplitude is defined in % of the nominal current (see: CURRENT
command). Depending on internal calculations the setting at higher frequencies is only possible in steps. Al­ways the next higher step is chosen.

CAUTION: The PPWM and IPWM parameters influence the effect of the dither setting. These param­eters should not be changed again after the dither has been optimized.

CAUTION: If the PWM frequency is less than 500 Hz, the dither amplitude should be set to zero.

The DITHER is a superimposed signal to reduce the hysteresis. This function is defined by the amplitude and frequency.
The DITHER frequency should not be confused with the PWM frequency. In some proportional valve documentations a
mistake is done by the definition of the DITHER / PWM frequency. It is recognizable by missing information about the
DITHER amplitude.

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Command

Parameters

Unit

Group

PWM X

x= 61… 2604

Hz

STD

Command

Parameters

Unit

Group

ACC x

x= ON|OFF

-

EXP

5.5.4 PWM (PWM frequency)

The frequency can be changed in the defined steps (61 Hz, 72 Hz, 85 Hz, 100 Hz, 120 Hz, 150 Hz, 200 Hz,
269 Hz, 372 Hz, 488 Hz, 624 Hz, 781 Hz, 976 Hz, 1201 Hz, 1420 Hz, 1562 Hz, 1736 Hz, 1953 Hz, 2232 Hz
and 2604 Hz). The optimum frequency depends on the valve.

Attention: The PPWM and IPWM parameters should be adapted when using low PWM frequencies
because of the longer dead times which forces a reduced stability of the closed loop control.

5.5.5 ACC (Auto adaptation of the closed loop current controller)

Operation mode of the closed loop current control.

ON: In automatic mode PPWM and IPWM are calculated depending on the preset PWM-frequency.
OFF: Manual adjustment.

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Command

Parameters

Unit

Group

PPWM X

IPWM X

x= 0… 30

x= 1… 100

-

-

ACC=OFF

Command

Description

Unit

WR

WA

W

C

U

IA

IB

RV+

Command value (real Unit)
Scaled command value
Command value after ramp function
Control signal
Output signal to power stage
Current to solenoid A
Current to solenoid B
Reference supply voltage

V
%
%
%
%
mA
mA
V

5.5.6 PPWM (Solenoid current controller P gain)

5.5.7 IPWM (Solenoid current controller I gain)

The PI current controller for the solenoids is parameterized with these commands.

CAUTION: These parameters should not be changed without adequate measurement facilities and
experiences.

Attention, if the parameter ACC is set to ON, these adjustments are done automatically.

If the PWM frequency is < 250 Hz, the dynamic of the current controller has to be decreased.
Typical values are: PPWM = 1… 3 and IPWM = 40… 80.

If the PWM frequency is > 1000 Hz, the default values of PPWM = 7 and IPWM = 40 should be chosen.

5.6 Process data (Monitoring)

The process data are the variable values which can be continuously observed on the monitor or on the oscillo­scope.

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Source

Fault

Characteristics

Command signal PIN 9 (LIM)

Out of range

The power stage is deactivated.

Solenoid A PIN 3 / 4
Solenoid B PIN 1 / 2

Broken wire

The power stage is deactivated.

EEPROM
(monitored during power on procedure)

Data error

The power stage is deactivated.
The module can be activated by

saving new parameters (press­ing of the SAVE Button).

FAULT

CAUSE / SOLUTION

ENABLE is active, the
module does not re­spond, and the READY
LED is off.

Probably the power supply is disconnected or the ENABLE signal is not present.
If there is no power supply there is also no communication via our operating program.

If the connection to the WPC-300 exists, the power supply is also available. In this
case the availability of the ENABLE signal can be checked via the monitor.

ENABLE is active, the
READY LED is flashing.

The flashing READY LED indicates that a fault is detected by the module. The fault
could be:

 Failure detection at command signal input (LIM command).
 A broken cable or incorrect wiring to the solenoids.
 Internal data error: execute the command / press the button SAVE to delete the

data error. The system reloads the DEFAULT data.

With the WPC-300 operating program the failure can be localized directly via the
monitor.

6 Appendix

6.1 Failure monitoring

Following possible error sources are monitored continuously when SENS = ON / AUTO:

6.2 Troubleshooting

Initial situation is an operable status of the device and existing communication between the module and the
WPC-300 program. Furthermore, the parameterization of the valve control has to be done with the assistance
of the valve data sheets.

The RC mode in monitor can be used to analyze faults.

CAUTION: If using the RC (Remote Control) mode, all safety aspects have to be checked solidly.
In this mode the module is actuated directly and the machine control has no influence on the
module.

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6.3 Description of the command structure

The command structure:

[nnnn:i x] or
[nnnn x]

Meaning:

nnnn - used for an arbitrary command name
nnnn: - used for an arbitrary command name, expandable by an index.

Indexed commands are indicated by the sign “:”

I or I - i=dummy is for the index. E.g.an index can be „A“or„B“, depending on the direction.
x - parameter value, in case of special commands more than one parameter are possible.

Examples:

MIN:A 2000 nnnn = “MIN”, i = “A” and x = “2000”

OFFSET 50 nnnn = „OFFSET“ and x = „50“

C:IC 2000 nnnn = “C”, i = “IC” and x = “2000”

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7 Notes

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