POS-124-PDP

W.E.ST. Elektronik GmbH 

Technical Documentation 

POS-124-A-PDP 

POS-124-I-PDP 

Two axes positioning and synchronisation control module with 

integrated profibus interface and SSI sensor interface


CONTENTS 

1 General Information ............................................................................................................................................. 4 

1.1 Order number .............................................................................................................................................. 4 

1.2 Scope of supply ........................................................................................................................................... 4 

1.3 Accessories ................................................................................................................................................. 4 

1.4 Symbols used .............................................................................................................................................. 5 

1.5 Using this documentation ............................................................................................................................ 5 

1.6 Legal notice ................................................................................................................................................. 5 

1.7 Safety instructions ....................................................................................................................................... 6 

2 Characteristics ..................................................................................................................................................... 7 

2.1 Device description ....................................................................................................................................... 8 

3 Use and application ............................................................................................................................................. 9 

3.1 Installation instructions ................................................................................................................................ 9 

3.2 Typical system structure ............................................................................................................................ 10 

3.3 Method of operation ................................................................................................................................... 10 

3.4 Commissioning .......................................................................................................................................... 12 

4 Technical description ......................................................................................................................................... 13 

4.1 Input and output signals ............................................................................................................................. 13 

4.2 LED definitions ........................................................................................................................................... 14 

4.3 Circuit diagram ........................................................................................................................................... 15 

4.4 Typical cabling ........................................................................................................................................... 16 

4.5 Connection examples ................................................................................................................................ 16 

4.6 Technical data ........................................................................................................................................... 17 

5 Parameters ........................................................................................................................................................ 18 

5.1 Parameter overview ................................................................................................................................... 18 

5.2 Parameter description ................................................................................................................................ 20 

5.2.1 LG (Changing the language for the help texts) ................................................................................. 20 

5.2.2 PDPADR (Profibus adress) ............................................................................................................... 20 

5.2.3 MODE (Switching between parameter groups) ................................................................................. 20 

5.2.4 SENS (Module monitoring) ............................................................................................................... 21 

5.2.5 STROKE1 /STROKE2 (Full stroke) ................................................................................................... 21 

5.2.6 VRAMP1 /VRAMP2 (Ramp time for external speed demand) .......................................................... 21 

5.2.7 VMODE1 / VMODE2 (Switching over the control mode)................................................................... 22 

5.2.8 VMAX1 / VMAX2 (Maximum speed in NC Mode) ............................................................................. 22 

5.2.9 POL1 / POL2 (Output polarity) .......................................................................................................... 23 

5.2.10 EOUT1 / EOUT2 (Output signal in case of error) .............................................................................. 23 

5.2.11 INPX (Sensor type define) ................................................................................................................ 24 

5.2.12 SSI:OFFSET (Sensor offset) ............................................................................................................. 24 

5.2.13 SSI:POL (Direction of the sensor signal) ........................................................................................... 24 

5.2.14 SSI:RES (Signal resolution) .............................................................................................................. 25 

5.2.15 SSI:BITS (Number of bits) ................................................................................................................. 25 

5.2.16 SSI:CODE (Signal coding) ................................................................................................................ 25 

5.2.17 AIN (Analogue input scaling) ............................................................................................................. 26 

5.2.18 A1 / A2 (Acceleration time) ............................................................................................................... 27 

5.2.19 D1 / D2 (Deceleration / braking distance) ......................................................................................... 27 

5.2.20 V01 / V02 (Loop gain setting) ............................................................................................................. 28 

5.2.21 CTRL1 / CTRL2 (Deceleration function characteristic) ..................................................................... 29 

5.2.22 GL: P (gain of the synchronization in SDD mode) ............................................................................. 30 

5.2.23 GL: V0 (gain of the synchronization in NC mode) ............................................................................. 30 

5.2.24 GL:T1 (Time constant of the synchronisation control) ....................................................................... 30 

5.2.25 GL:E (Window for the synchronization error) .................................................................................... 30 

Page 2 of 45 POS-124-*-PDP-1121 13.02.2013


5.2.26 HAND1 / HAND2 (Manual speed) ..................................................................................................... 31 

5.2.27 MIN / MIN2 (Overlap compensation) ................................................................................................. 32 

5.2.28 MAX1 / MAX2 (Limitation) ................................................................................................................. 32 

5.2.29 TRIGGER (Response threshold for the MIN parameter) ................................................................... 32 

5.2.30 OFFSET1 / OFFSET2 (Zero correction) ............................................................................................ 33 

5.2.31 INPOS:S1 / INPOS:S2 (In position window) ...................................................................................... 33 

5.2.32 INPOS:D1 / INPOS:D2 (following error window) ............................................................................... 33 

5.2.33 PROCESS DATA (Monitoring) .......................................................................................................... 34 

6 Appendix ............................................................................................................................................................ 35 

6.1 Failure monitoring ...................................................................................................................................... 35 

6.2 Troubleshooting ......................................................................................................................................... 35 

6.3 Description of the command structure ........................................................................................................ 37 

7 Profibus DP interface ......................................................................................................................................... 38 

7.1 Profibus functions....................................................................................................................................... 38 

7.2 Installation .................................................................................................................................................. 38 

7.3 GSD Configuration File .............................................................................................................................. 38 

7.4 Description Profibus DP interface .............................................................................................................. 39 

7.5 Commands via PROFIBUS ........................................................................................................................ 40 

7.5.1 Command map .................................................................................................................................. 40 

7.5.2 Definition of the control bits: .............................................................................................................. 41 

7.6 DATA send to PROFIBUS ......................................................................................................................... 42 

7.6.1 Feedback map ................................................................................................................................... 42 

7.6.2 Definition of the status bits: ............................................................................................................... 43 

8 Notes.................................................................................................................................................................. 44 


1 General Information 

1.1 Order number 


POS-124-A-PDP-1121 1 triple stage module with digital SSI-interface with analogue ±10 V 

differential output, housing width 67,5 mm 

POS-124-I-PDP-1121 triple stage module with digital SSI-interface with analogue 4… 20 mA 

output, housing width 67,5 mm 

Alternative products: 

POS-124-A-PDP-S1-1121 double stage module without digital SSI-interface with analogue ±10 V 

differential output, 45 mm housing width 

POS-124-I-PDP-S1-1121 double stage module without digital SSI-interface with analogue 

4… 20 mA output, 45 mm housing width 

1.2 Scope of supply 

The scope of supply includes the module including 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 

RS232-SO - Programming cable with RS232 interface 

USB-SO - Programming cable with USB interface 

WPC-300 - Start-Up-Tool (download: www.w-e-st.de/produkte/software) 

PDP-Plug - Profibus connector with switchable terminating resistors 

1 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. 


1.4 Symbols used 

General information 

Safety-related information 

1.5 Using this documentation 

Structure of the documentation: 


The standard product is descibed up to chapter 6. The extensions like POWER STAGE or 

SSI-INTERFACE are described in the chapters ADDITIONAL INFORMATION. 

1.6 Legal notice 

W.E.St. Elektronik GmbH 

Gewerbering 31 

D-41372 Niederkrüchten 

Tel.: +49 (0)2163 577355-0 

Fax.: +49 (0)2163 577355 -11 

Homepage: www.w-e-st.de or www.west-electronics.com 

EMAIL: info@w-e-st.de 

Date: 13.02.2013 

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 copyright. 


1.7 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, contamination 

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. 


2 Characteristics 


This electronic module has been developed for controlling hydraulic positioning drives. 

Both axes are controlled complete autonomous via the Profibus. Optionally an interconnection to a two 

axes synchronised system is intended. 

The differential outputs are covered for activation of constant valves with integrated or external 

electronics (differential input). Intended is this module for the connection of analogue way sensors 0...10V 

or 4...20mA (scalable) or digital SSI sensor interfaces. 

The internal control signals operating states and error conditions via Profibus to the higher-level control. 

The operation is signaled by a switch output. 

Typical applications: Positioning control or synchronization control with hydraulic axes. 

Features 

• Two independent positioning axes 

• Can be combined for synchronization controls 

• Command position parameter, actual value response, on loop control byte and status byte via 

fieldbus Profibus DP 

• Principle of stroke-dependent deceleration for the shortest positioning time or NC profile gen- 

erator for constant speed 

• Analogue or digital (SSI) actual value registration for both axes 

• Superimposed synchronization controller as PT1 actuator 

• Usable with zero lapped control valves 

• Fault diagnosis and extended function checking 

• Simplified parameterization with WPC-300 software version 3.2 


2.1 Device description 

D-outputs 

Ready 

24 V 

0 V 

Enable 

D-inputs 

99,0000 mm 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

Made in Germany 

Date: Add.: 

ID: 

V: 

Analogue 

GND 

GND 

Pos. 1 

Pos. 2 

W.E.ST. Elektronik 

A Differential 

B output 

D-41372 Niederkrüchten 

Homepage: http://www.w-e-st.de 

Typenschild und Anschlussbelegung 

Type plate and terminal pin assignment 


LEDs 

RS232 

Interface 

1 2 3 4 17 18 19 20 33 34 35 36 

5 6 7 8 21 22 23 24 37 38 39 40 

W.E.ST. 

Page 8 of 45 POS-124-*-PDP-1121 13.02.2013 

Ready 

Status 

Online 

Profibus 

9pol SUBD 

9 10 11 12 25 26 27 28 41 42 43 44 

13 14 15 16 29 30 31 32 45 46 47 48 

67,5000 mm 

121,0000 mm 

114,0000 mm 

Klemmblöcke (steckbar) 

Terminals (removable) 

PROFIBUS Buchse 

PROFIBUS connector

3 Use and application 

3.1 Installation instructions 


• 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 control 

and regulation 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 shielded. 

• 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 

possible. 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 interference 

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. 


3.2 Typical system structure 


This minimal system consists of the following components: 

(*1) proportional valve 

(*2) hydraulic cylinder 

(*3) position sensor 

(*4) POS-124-PDP control module 

(*5) interface to PLC with analogue and digital signals 

3.3 Method of operation 

This control module supports simple point-to-point positioning with hydraulic drives. The system works 

based on the principle of stroke-dependent deceleration, i.e. the control gain (deceleration stroke) is set 

via parameters D:A and D:B. Alternatively the loop gain will be used in NC mode. 

The deceleration characteristics can be set linearly (LIN) or approximately quadratically (SQRT1) via the 

CTRL parameter. For normal proportional valves SQRT1 is the input setting. 

For control valves with a linear flow curve it depends on the application. If LIN is selected for these valves 

a significantly shorter deceleration distance can often be set (D:A and D:B). 



Positioning sequence: 

The positioning is controlled via Profibus. After releasing (ENABLE input), the command 

position is set to the actual position of the sensor and the axis stays in closed loop position control 

mode. The READY output indicates that the system is generally ready for operation. When setting the 

START-signal, the preset command value will be taken over. The axis immediately will drive to this new 

command position and indicates reaching it by setting the InPos output. 

The InPos output stays active as long as the axis is within the preset InPos window and the START input 

is active. The driving velocity is forced by preset parameter, too. 

The axis can be driven in manual mode (START is off) using the control bits HAND+ or HAND-. The 

velocity is programmable. When the HAND signal is deactivated, the command position is set to the actual 

position and the system stays in closed loop position control mode. 

Setting the synchronous bit (GL) will synchronize both axes and the synchronization controller is overriding 

the position controller of axis 2. Axis 2 is now following axis 1 according to the master-slave-principle. 

Influences on positioning accuracy: 

The positioning accuracy is determined by the hydraulic and mechanical conditions. The right choice of 

valve is therefore a decisive factor. In addition, two mutually contradictory requirements (short position 

time and high accuracy) must be taken into account when designing the system. 

The electronic limitations lie mainly in the resolution of the analogue signals, although with our modules a 

resolution of < 0.01% only needs to be considered with long positions. In addition, the linearity of the individual 

signal points (PLC, sensor and control module) must be considered. The worst-case scenario is 

that a system-specific absolute fault occurs. 

The repeat accuracy is, however, not affected by this. 

V+ 

V+ 

volumetric flow P-A and B-T 

MAX:A 

A:A D:A 

D:B 

control direction 

driving out 

control direction 

driving in 

MAX:B 


A:B

3.4 Commissioning 

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 metal 

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 cabling. Switch the device off 

immediately and check the cabling. 

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. 

Further commissioning and diagnosis are supported by the operating software. 

Pre-parameterisation Now set up the following parameters (with reference to the system design and circuit 

diagrams): 

The STROKE, POSITION, SENSOR SETTING, POLARITY, ACCELERATION 

and DECELERATION. 

Pre-parameterisation is necessary to minimise the risk of uncontrolled movements. 

Parameterise specific settings for the control element (MIN for following error 

compensation and MAX for maximum velocity). 

Reduce the speed limitation to a value which is uncritical for the application. 

Control signals Check the control signal with a voltmeter. The control signals (PIN 15 to PIN16 

and PIN19 to PIN20) lies in the range of ± 10V. In the current state it should be 

0V. Alternatively, if current signals are used, approx. 0 mA should flow. 

CAUTION! This signal depends on the EOUT setting. 

Profibus communication Activate the profibus communication and check whether the right values and bits 

are send to the module. 

Switching on the hydraulics 

Activating ENABLE 

The hydraulics can now be switched on. Since the module is not yet generating a 

signal the drive should be at a standstill or drift slightly (leave its position at a slow 

speed). 

CAUTION! The drive can now leave its position and move to an end position at 

full speed. Take safety measures to prevent personal injury and damage. 

The drive is in the current position (with ENABLE the actual position is accepted 

as the required position). Should the drive move to an end position the polarity is 

probably wrong. 

Activating START With the start signal the demand value on the analogue demand value input is accepted 

and the axis moves to the predefined target position. 

If START is disabled the axis stops in the preset deceleration distance D:S. 

Manual (HAND) operation If START is disabled the axis can be moved manually with HAND+ or HAND- . 

After disabling the HAND signal, the axis stops in a controlled manner at the current 

position. 

Optimise controller Now optimise the controller parameters according to your application and your 

requirements. 


4 Technical description 

4.1 Input and output signals 

Connection Supply 

PIN 3, PIN 31 

and PIN 35 

PIN 4, PIN 32 

and PIN 36 


Power supply (see technical data) 

0 V (GND) connection. 

Caution, PIN 4 is connected internally to PIN 11 (and also possibly to PIN 12 depending on 

the model). These connections serve as a reference potential for the analogue sensor or 

demand value signals. 

Connection Analogue signals 

PIN 13 Analogue position actual value (X1), range 0… 100% corresponds to 0… 10V or 4… 20 mA 

PIN 14 Analogue position actual value (X2), range 0… 100% corresponds to 0… 10V or 4… 20 mA 

PIN 15 / 16 Analogue differential output for activation of the axis 1: 

-100...100% corresponds to -10...10V. 

PIN 19 / 20 Analogue differential output for activation of the axis 2: 

-100...100% corresponds to -10...10V. 

Connection SSI sensors 

PIN 37-40 

PIN 33, 34 

PIN 41-44 

PIN 47, 48 

Interface 1 to the SSI sensor. RS422 interface and power supply 

Interface 2 to the SSI sensor. RS422 interface and power supply 

Connection Digital inputs and outputs 

PIN 8 

Enable input: 

This digital input signal initializes the application. The signal will be approved in connection 

with the software enable the corresponding axis. 

PIN 2 Synchronous error output (only active in synchronous mode): 

ON: Slave axis within the error window (GL:E) 

PIN 1 

OFF: Slave axis outside the error window (GL:E) 

READY output: 

ON: The module is enabled; there are no discernable errors. 

OFF: Enable (PIN 8) is disabled or an error (sensor or internal error) has been detected. 


4.2 LED definitions 


LEDs Description of the LED function 

GREEN Identical to the READY output. 

OFF: no power supply or ENABLE is not activated 

ON: System is ready for operation 

Flashing: Error discovered (valve solenoid or 4… 20 mA). 

The error of one axis results to a flashing LED. 

YELLOW Only active in synchronous mode: 

OFF: Slave axis outside the error window 

GREEN 

(right side) 

ON: Slave axis within the error window 

Profibus connection. 

OFF: No Profibus communication 

ON: Profibus communication in prozess 


4.3 Circuit diagram 

Profibus DP 

ANA Feedback 

Position 1 

0 V 

SSI Feedback 

Position 1 

ANA Feedback 

Position 2 

0 V 

SSI Feedback 

Position 2 

Enable 

0..10V 

4..20mA 

0 V 

0..10V 

4..20mA 

0 V 

13 

11 

33 

34 

37 

38 

39 

40 

14 

11 

47 

48 

41 

42 

43 

44 

8 

9 

24 V 

0 V 

CLK+ 

CLK- 

DATA+ 

DATA- 

24 V 

0 V 

CLK+ 

CLK- 

DATA+ 

DATA- 

Profibus 

SUBD 

9polig 

Speed 

via Feldbus 

Position 

via Feldbus 

Input Scaling 

Commands: 

AIN:W 

SSI Sensor 

Commands: 

SSI:RES 

SSI:BITS 

SSI:CODE 

SSI:POL1 

SSI:OFFSET1 

Input Scaling 

Commands: 

AIN:W 

SSI Sensor 

Commands: 

SSI:RES 

SSI:BITS 

SSI:CODE 

SSI:POL2 

SSI:OFFSET2 

24 V input 


ws1 

x2 

v1 

Speed 

INPX = ANA 

INPX = SSI 

INPX = ANA 

x2 

INPX = SSI 

Profil Generator 

Commands: 

- STROKE 

VMODE = NC 

VMODE = SDD 

Commands: 

- TS (sample time) 

- MODE (Expert or Standard) 

- EOUT (Error Mode) 

- INPOS (InPos output) 

w1 

- 

POS-124-A/I-PDP 

xd1 

x1 

Control Function 

Commands: 

- A:A and A:B 

- D:A and D:B 

Control program 

AXIS 2 

Output Adaptation 

Commands: 

- MIN: A and B 

- MAX: A and B 

- TRIGGER 

- OFFSET 

- POL 

Internal Power 

VMODE = SDD 

3,5 mm JISC-6560 Buchse 

PE via DIN-RAIL 


x1 

x2 

Output 

limitation 

AXIS 1 

Synchronous Controller 

Commands: 

- GL:P 

- GL:T1 

- GL:E 

RS232 C 

9600 Baud 

1 Stopbit 

no parity 

u2 

u1 

DC 

24 V output 

24 V output 

DC 

Output: A 

Output: B 

Enable Sync. 

via Feldbus 

Output: A 

Output: B 

24 V 

0 V 

35 

31 

3 

4 

32 

36 

15 

16 

12 

19 

20 

18 

1 

2 

Differentialinput 

I-Version: 4... 20 mA 

PIN 15 = +, PIN 12 = GND 

Ready 

24 V 

PELV 

0 V 

Differentialinput 

I Version: 4... 20 mA 

PIN 19 = +, PIN 18 = GND 

Synchron 

Error

4.4 Typical cabling 

0..10V, 4..20mA 

sensor position 

13 = X1, 14 = X2 

ENABLE 

+/- 10 V (4...20mA) 

to control valve 1 

4.5 Connection examples 

SPS / PLC 0... 10 V speed input signal 

+In PIN 10 

-In PIN 9 

GND PIN 11 

PE 

SPS / PLC 0... 10 V command and feedback signal 

+In PIN 13 or PIN 14 

In PIN 12 (GND) 

Valve (6 + PE plug) with OBE electronics 

Module 

PIN 12 

PIN 15 

PIN 16 

A : 24 V supply 

B : 0 V supply 

C : GND or enable 

D : + differential input 

E : - differential input 

F : diagnostics 

PE - 


1 

5 

9 

13 

2 

6 

10 

14 

3 

7 

11 

15 

4 

8 

12 

16 

17 

21 

29 

18 

22 

Profibus 

9pol Buchse 

30 

z. B. 24 V 

19 

23 

31 

z. B. 24 V 

24V power 

0V supply 

+/- 10 V (4...20mA) 

to control valve 2 


20 

24 

32 

33 

37 

41 

45 

34 

38 

42 

46 

35 

39 

43 

47 

36 

40 

44 

48 

PE Klemme 

GND 

+24 V DC 

power supply 

communication modul 

+In PIN 13 or 14 

PIN 12 (GND) 

+24 V DC 

GND 

SSI 1 

sensor interface 

CLK+ 

CLK- 

DATA+ 

DATA- 

DATA- 

DATA+ 

CLK- 

CLK+ 

SSI 2 

sensor interface 

GND 

+24 V DC 

PLC or sensor with 4... 20 mA (two wire connection) 

+In PIN 13 or 14 

PIN 12 (GND) 

AIN:W 2000 1600 2000 C ( für 0... 100%) 

PLC or sensor with 4... 20 mA (three wire connection) 

AIN:W 2000 1600 2000 C ( für 0... 100%)

4.6 Technical data 

Supply voltage 

Current requirement 

External protection 

Digital inputs 

Input resistance 


[VDC] 

[mA] 

[A] 

[V] 

[V] 

[kOhm] 

Digital outputs [V] 

Analogue inputs (sensor and 

demand value signal) 

Signal resolution 

Analogue outputs 

Voltage 


Current 


[V] 

[V] 

[mA] 

[%] 

[V] 

[mA] 

[%] 

[mA] 

[%] 

24 (±10 %) 

500 

1 medium time lag 

logic 0: < 2 V 

logic 1: > 10 V,current consumption 

< 0,1 mA 

25 

logic 0: < 2 V 

logic 1: > 12 V; max. 10 mA 

0… 10. 33 kOhm 

4… 20. 250 Ohm 

0.01(internally 0.0031) inc. oversampling 

2 x 0… 10; Differential output 

5 (max. load) 

0.024 

4… 20; 390 Ohm maximum load 

0.024 

SSI interface - RS-422 Spezifikation, 150 kBaud 

Controller sample time [ms] 1 

Serial interface 

Profibus DP 

Baud rate 

ID Number 

RS 232C, 9600… 57600 Baud, 1 stop 

bit, no parity, Echo Mode 

9.6,19,2,93.75,187.5,500,1500,3000 

6000, 12000 kbits/s 

1810h 

Housing Snap-on module to EN 50022 

Protection class 

Temperature range 

Storage Temperature 

Humidity 

[°C] 

[°C] 

[%] 

PA 6.6 polyamide 

Flammability class V0 (UL94) 

IP20 

-10… 50 

-20... 70 

5 Parameters 

5.1 Parameter overview 


Command Default Unit Description 

LG GB - Changing language help texts. 

PDPADR 126 - Address of the unit at the Profibus. 

MODE STD - Mode parameter. 

SENS ON - Activation and disabling of internal failure monitoring 

functions. 

INPX SSI - Switching between SSI and analog sensors. 

STROKE1 

STROKE2 

VRAMP1 

VRAMP2 

VMODE1 

VMODE2 

VMAX1 

VMAX2 

POL1 

POL2 

EOUT1 

EOUT2 

SSI:OFFSET1 

SSI:OFFSET2 

SSI:POL1 

SSI:POL2 

X = 10...10000 mm Working stroke of the sensor. 

100 ms Ramp function for external speed input. 

SDD - Control structure for positioning process. 

50 mm/s Maximum speed in NC mode. 

+ - Reversal of output polarity. 

0 0,01% Error output signal. 

0 10 nm Position offset 

+ - Sensor polarity 

SSI:RES 500 10 nm Resolution of the sensors (the same for both) 

SSI:BITS 24 - Number of transmitted bits (the same for both) 

SSI:CODE GRAY - transfer Encoding (the same for both) 

AIN:I 

A 

B 

C 

X 

A1:I 

A2:I 

D1:I 

D2:I 

V01:I 

V02:I 

CTRL 1 

CTRL 2 

GL:P 

GL:T1 

GL:E 

HAND1:I 

HAND2:I 

10000 

10000 

10000 

V 

:A 100 

:B 100 

:A 25 

:B 25 

:S 10 

:A 10 

:B 10 

- 

- 

0,01 % 

- 

ms 

mm 

mm 

mm 

1/s 

1/s 

Analogue input scaling for X1 and X2. 

Acceleration times. 

Deceleration distance 

Deceleration distance 

Emergency deceleration distance 

Loop gain setting. 

sqrt1 - Specification of control characteristics. 

48 

80 

200 

:A 3330 

:B -3330 

0,01 

ms 

µm 

0,01% 

Definition of the synchronization actuator. GL:P 

adjusted the gain, GL:T1 effects a decelerated action 

of the actuator (revised stability) and .GL:E for 

error-window in synchronous run (out of window 

GL-Error-Bit is set on the Profibus) 

Output signal in manual mode. 


MIN1:I 

MIN2:I 

MAX1:I 

MAX2:I 

TRIGGER1 

TRIGGER2 

OFFSET1 

OFFSET2 

INPOS1:I 

INPOS2:I 


0 

0 

10000 

10000 

200 

200 

0 

0 

200 

200 

0,01 % 

0,01 % 

0,01 % 

0,01 %% 

0,01 % 

0,01 %% 

0,01 % 

0,01 %% 

µm 

µm 

Zero point setting /following error compensation. 

Maximum output signal limitation. 

Trigger threshold for activating the following error 

compensation (MIN). 

Offset value (added to the output signal).Axis 1 and 

axis 2 separate definable. 

Range for InPos signal. 


5.2 Parameter description 


5.2.1 LG (Changing the language for the help texts) 

Command Parameters Unit Group 

LG x x= DE|GB - STD 

Either German or English can be selected for the help texts. 

CAUTION: After changing the language settings the ID button (SPEED BUTTON) in the menu 

bar (WPC-300) must be pressed (module identification). 

5.2.2 PDPADR (Profibus adress) 


PDPADR X x= 1...126 - STD 

Slave address in the Profibus network. 

5.2.3 MODE (Switching between parameter groups) 


MODE x x= STD|EXP - STD 

This command changes the operating mode. Various commands (defined via STD/EXP) are blanked out 

in Standard Mode. The commands in Expert Mode have a more significant influence on system behaviour 

and should accordingly be changed with care. 


5.2.4 SENS (Module monitoring) 



SENS x x= ON|OFF - STD 

This command is used to activate and disable monitoring functions (4… 20 mA sensors and internal 

module monitoring). 

ON: Monitor function is activ. 

OFF: Failures are ignored. 

Normally, monitoring is always active as otherwise no errors are signalled via the PIN 1 

(READY) output. It can, however, be disabled for fault finding. 

5.2.5 STROKE1 /STROKE2 (Full stroke) 


STROKE1 X 

STROKE2 X 

x= 10… 10000 mm STD 

This command defines the full stroke, which corresponds to 100% of the input signal. If the demand is set 

incorrectly, this leads to incorrect system settings, and the dependent parameters such as speed and 

gain cannot be calculated correctly. 

5.2.6 VRAMP1 /VRAMP2 (Ramp time for external speed demand) 


VRAMP1 X 

VRAMP2 X 

x= 1… 2000 ms STD 

The rate of change of the external speed demand can be limited by this ramp time. The command is only 

active if external speed demand (VS = EXT) has been parametrised. 



5.2.7 VMODE1 / VMODE2 (Switching over the control mode) 


VMODE1 X 

VMODE2 X 

x= SDD|NC EXP 

The fundamental control structure can be changed with this parameter. 

SDD: Stroke-Dependent Deceleration. In this mode, stroke-dependent deceleration is activated. This 

mode is the default mode and is suitable for most applications. With stroke-dependent deceleration 

the drive comes to a controlled stop at the target position. From the set deceleration 

point the drive then switches to control mode and moves accurately to the desired position. 

This control structure is very robust and reacts insensitively to external influences such as fluctuating 

pressures. 

One disadvantage is that the speed varies with the fluctuating pressure as the system runs 

under open-loop control. 

NC: Numerically Controlled. In this mode a position profile is generated internally. The system always 

works under control and uses the following error to follow the position profile. The magnitude 

of the following error is determined by the dynamics and the set control gain. The advantage 

is that the speed is constant (regardless of external influences 2 ) due to the profile 

demand. Because of continuous control, it is necessary not to run at 100% speed, as otherwise 

the errors cannot be corrected. 80% of the maximum speed is typical although especially 

the system behaviour and the load pressure should be taken into account when specifying the 

speed. 

5.2.8 VMAX1 / VMAX2 (Maximum speed in NC Mode) 


VMAX1 X 

VMAX2 X 

x= 1… 5000 mm/s VMODE = NC 

Specification of the maximum speed in NC Mode. This value is defined by the drive system and should be 

specified as precisely as possible (not too high under any circumstances) 3 . The maximum speed is 

scaled by means of the VELO value or via the external speed demand. The command is only active if the 

VMODE has been parametrised to NC. 

2 

There are deviations due to external influences which are then compensated for. The time response is defined by 

the system dynamics. 

3 

If the retraction speed and the outward speed are different, the smaller one has to be used 



5.2.9 POL1 / POL2 (Output polarity) 


POL1 X 

POL2 X 

x= +|- - STD 

This command enables the output signal polarity to be reversed. 

5.2.10 EOUT1 / EOUT2 (Output signal in case of error) 


EOUT1 X 

EOUT2 X 

x= -10000… 10000 0,01% EXP 

Error output value. A value (degree of valve opening) for use in the event of a sensor error can be defined 

here. This function can be used if, for example, the drive is to move to one of the two end positions (at the 

specified speed) in case of a sensor error. 

|EOUT| = 0 The output is switched off in the event of an error. This is normal behaviour. 

CAUTION! If the output signal is 4… 20 mA, the output is switched off if |EOUT| = 0. If a 

null value = 12 mA is to be output in the event of an error, EOUT must be set to 1 4 . 

CAUTION! The output value defined here is stored permanently (independently of the parameter 

set). The effects should be analysed by the user for each application from the 

point of view of safety 

CAUTION! If EOUT is activated, the HAND mode should not be used. After deactivating 

the HAND mode the output will be set to the programmed EOUT value. 

. 

4 This is necessary if using valves without error detection for signals lower than 4 mA 


5.2.11 INPX (Sensor type define) 



INPX X x= SSI|ANA STD 

With this parameter the appropriate sensor type can be activated. 

SSI: The SSI sensor interfaces are active. The SSI sensors have to be adjusted via the SSI commands 

to the sensors. The relevant sensor data must be available. 

ANA: The analog sensor interfaces (0 ... 10 V or 4 ... 20 mA) are active. The sensors are scaled with 

the commands AIN: X 

The SSI interface is suitable for digital position sensor. The internally processed accuracy is 1 micron. 

CAUTION: It can only be used SSI sensors of the same type, ie the resolution of the sensor, 

the number of bits transmitted and the transmission coding must be the same! 

5.2.12 SSI:OFFSET (Sensor offset) 


SSI:OFFSET1 X 

SSI:OFFSET2 X 

This command is a sensor offset (zero point of the sensor). 

x= -1000000… 1000000 µm INPX = SSI 

5.2.13 SSI:POL (Direction of the sensor signal) 


SSI:POL1 X 

SSI:POL2 X 

x= +|- - INPX = SSI 

To reverse the working direction of the sensor, with this command, the polarity can be changed. 

Example: Sensor Length = 200 mm, reverse the direction of work is required. 

Set SSI: POL to "-" (internally, the sensor position is subtracted from the stroke ). 


5.2.14 SSI:RES (Signal resolution) 



SSI:RES X x= 100… 10000 0,01 µm INPX = SSI 

This command defines the signal resolution of the sensor. Data entry has a resolution of 10 nm (nanometers 

or 0.01 micron). If the sensor has one micron resolution, the value must be set to 100. This makes it 

possible to scale rotational sensors. 

Take the data from the sensor data sheet. 

Caution: The signal resolution for both SSI sensors must be equal. 

5.2.15 SSI:BITS (Number of bits) 


SSI:BITS X x= 8… 31 bits INPX = SSI 

With this command the number of data bits can be set. 


Caution: The number of bits for both SSI sensors must be equal. 

5.2.16 SSI:CODE (Signal coding) 


SSI:CODE X x= GRAY|BIN - INPX = SSI 

With this command the signal coding can be set. 


Caution: The signal coding for both SSI sensors must be equal. 


5.2.17 AIN (Analogue input scaling) 



AIN:I 

A 

B 

C 

X 

i= X1|X2 

a= -10000… 10000 

b= -10000… 10000 

c= -700… 10000 

x= V|C 

- 

- 

0.01% 

- 

This command can be used to scale the individual inputs. The following linear equation is used for 

scaling. 

= ∙ − 

The “c” value is the offset (e.g. to compensate the 4 mA in the case of a 4… 20 mA input). The variables a 

and b define the gain factor. 

e.g.: 2.345 correspond to: a = 2345, b =1000 

The internal measuring resistor for measuring the current (4… 20 mA) is activated via the x value and the 

evaluation switched over accordingly. 

Typical settings: 

Command Input Description 

AIN:X1 1000 1000 0 V 0… 10V Range: 0… 100% 

AIN:X1 10 8 1000 V 

OR 

AIN:X1 1000 800 1000 V 

AIN:X1 10 4 500 V 

OR 

AIN:X1 1000 400 500 V 

AIN:X1 20 16 2000 C 

OR 

AIN:X1 2000 1600 2000 C 


STD 

1… 9V Range: 0… 100%; 1 V = 1000 used for the offset and gained by 10 / 

8 (10V divided by 8 V (9V -1V) 

0,5… 4,5V Range: 0… 100%; 0,5 V = 500 used for the offset and gained by 10 / 

4 (10V divided by 4 V (4,5V -0,5V) 

4… 20mA Range: 0… 100% 

The offset will be compensated on 20% (4 mA) and the signal (16 mA 

= 20mA – 4 mA) will be gained to 100% (20 mA).

5.2.18 A1 / A2 (Acceleration time) 



A1:I X 

A2:I X 

i= A|B 

x= 1… 5000 

Ramp function for the 1 st and 3 rd quadrants. 

The acceleration time for positioning is dependent on the direction. A corresponds to connection 15 and B 

corresponds to connection 16 (if POL = +). 

Normally A = flow P-A, B-T and B = flow P-B, A-T. 

For quadrants 2 and 4, parameters D:A and D:B are used as the deceleration distance demand. 

5.2.19 D1 / D2 (Deceleration / braking distance) 


ms 

ms 

STD 


D1:I X 

D2:I X 

i= A|B|S 

x= 1… 10000 

mm 

mm 

mm 

VMODE = SDD 

VMODE = SDD 

SDD + NC 

This parameter is specified in mm 5 . 

The deceleration distance is set for each direction of movement (A or B). The control gain is calculated 

internally depending on the deceleration distance. The shorter the deceleration distance, the higher the 

loop gain. A longer deceleration distance should be specified in the event of instability. 

Parameter D:S is used as the emergency stopping ramp when disabling the START signal. After disabling, 

a new target position (current position plus D:S) is calculated in relation to the speed and is specified 

as a demand value. 

G = 

Intern 

STROKE 

D 

i 

Calculation of control gain 

CAUTION: If the maximum position (POSITION command) is changed, the deceleration distance 

must also be adjusted. Otherwise this can result in instability and uncontrolled movements. 

5 CAUTION! With older modules this parameter was specified in % of the maximum path. Since data specification for 

this module has now been converted to mm the relationship between the path (PATH command) and these parameters 

must be taken into account.

5.2.20 V01 / V02 (Loop gain setting) 



V01:I X 

V02:I X 

i= A|B 

x= 1… 200 


s -1 

s -1 

VMODE = NC 

This parameter is specified in s -1 (1/s). 

In NC Mode the loop gain is normally specified rather than the deceleration distance 6 . 

The internal gain is calculated from this gain value together with the VMAX and POSITION parameters. 

Calculation of the internal control gain 

In NC Mode the following error at maximum speed is calculated by means of the loop gain. This following 

error corresponds to the deceleration distance with stroke-dependent deceleration. The conversion and 

therefore also the correct data demands related to the control system are relatively simple if the relationship 

described here is taken into account. 

6 The loop gain is alternatively defined as a KV factor with the unit (m/min)/mm or as Vo in 1/s. The conversion is KV 

= Vo/16.67. 

G 

v 

Di 

= 

V 

Intern 

max 

0 

STROKE 

= 

D 

i


5.2.21 CTRL1 / CTRL2 (Deceleration function characteristic) 


CTRL1 X 

CTRL2 X 

x= lin|sqrt1 

|sqrt2 

- STD 

The deceleration characteristic is set with this parameter. In the case of positively overlapped proportional 

valves the SQRT function should be used. The non-linear flow function of these valves is linearised by the 

SQRT 7 function. 

In the case of zero lapped valves (control valves and servo valves) the LIN or SQRT1 function should be 

used regardless of the application. The progressive characteristic of the SQRT1 function has better positioning 

accuracy but can also lead to longer positioning times in individual cases. 

LIN: Linear deceleration characteristic (gain is increased by a factor of 1). 

SQRT1: Root function for braking curve calculation. The gain is increased by a factor of 3 (in the target 

position). This is the default setting. 

SQRT2: Root function for braking curve calculation. The gain is increased by a factor of 5 (in the target 

position). This setting should only be used with a significantly progressive flow through the 

valve. 

Velocity 

CTRL = LIN 

Braking stroke 

D:A or D:B 

Stroke 

CTRL = SQRT 

7 The SQRT function generates constant deceleration and thus reaches the target position faster. This is achieved by 

increasing the gain during the deceleration process. 

Velocity 

CTRL = LIN 

1 Braking function with respect to stroke and time 

Deceleration time 

D:A or D:B 

CTRL = SQRT 


Time


5.2.22 GL: P (gain of the synchronization in SDD mode) 

5.2.23 GL: V0 (gain of the synchronization in NC mode) 

5.2.24 GL:T1 (Time constant of the synchronisation control) 

5.2.25 GL:E (Window for the synchronization error) 


GL:P X 

GL:V0 X 

GL:T1 X 

GL:E X 

X = 1… 10000 

X = 1… 200 

X = 1… 200 

X = 2… 10000 


mm 

s -1 

ms 

µm 

VMODE = SDD 

VMODE = NC 

These parameters are used to optimize the synchronization controller The SYNC-controller works as a 

PT1 compensator for optimized controlling of hydraulic drives. The parameter T1 effects a delayed action 

of the SYNC Controller. The stability of the compensator could be increased in critical cases with the up 

streamed T1 Filter. 

In SDD-mode is specified with GLP, the braking distance in mm. The gain will depend on the stopping 

distance is calculated internally. In short braking distance, the high gain is calculated. 

In the case of instability should be given a longer stopping distance. 

In NC-mode parameters of the GL: V0 is in s-1 (1 / s) specified. 

In this mode, the loop gain is entered. 

The parameter GL: T1 causes a delayed action of the synchronized controller. The stability of the controller 

can be increased by the upstream T1-filter in critical cases. 

The GL:E command defines a monitoring window in which the GL-Error message is displayed. The monitoring 

window is placed centrally on the required position value. The actual position value within this window 

is signalled by the GL-Error message at the status output (see signal description PROFIBUS). The 

positioning process is not influenced by this message. The control remains active. 

Master/Slave 

Profibus 

w 

x2 

x1 

Rampfunction 

w 

x2 

x1 

- 

- 

xw 

xk2 

A:A, A:B 

D:A, D:B 

GL:P, GL:V0 

GL:T1 

STD 

STD 

u2


5.2.26 HAND1 / HAND2 (Manual speed) 


HAND1:I X 

HAND2:I X 

i= A|B 

x= -10000… 10000 

0,01% 

0,01% 

The manual speeds are set with these parameters. Entering the speed and direction at will enables any 

switch input to be assigned. 

The drive moves in a controlled manner in the defined direction when the manual signal is active. After 

the manual signal has been disabled, the drive remains under closed loop control in the current position. 

In the event of a fault (position sensor fault) the drive can still be moved with the manual function. The 

output is zero after the manual signals have been disabled. 

The manual speed is limited by the speed demand (MIN evaluation) via the Profibus. 


STD


5.2.27 MIN / MIN2 (Overlap compensation) 

5.2.28 MAX1 / MAX2 (Limitation) 

5.2.29 TRIGGER (Response threshold for the MIN parameter) 


MIN1:I X 

MAX1:I X 

TRIGGER1 X 

MIN2:I X 

MAX2:I X 

TRIGGER2 X 

i= A|B 

x= 0… 6000 

x= 3000… 10000 

x= 0… 4000 

x= 0… 6000 

x= 3000… 10000 

x= 0… 4000 


- 

0,01% 

0,01% 

0,01% 

0,01% 

0,01% 

0,01% 

The output signal to the valve is adjusted by means of these commands. A kinked volume flow characteristic 

is used instead of the typical overlap step for the position controls. The advantage is better and more 

stable positioning behaviour. At the same time, non linear volume flow characteristics can also be adjusted 

with this compensation 8 . 

CAUTION: If there should also be adjustment options for dead zone compensation on 

the valve or valve amplifier, it must be ensured that the adjustment is performed either at 

the power amplifier or in the module. 

If the MIN value is set too high this has an effect on the minimum speed, which can then 

no longer be adjusted. In extreme cases this leads to oscillation around the controlled 

position. 

MIN:B 

MAX:B 

Output 

flow linearization 

Input 

STD 

MAX:A 

standard deadband compensation 

TRIGGER value 

8 Various manufacturers have valves with a defined linear curve: e.g. a kink at 40 or 60 % (corresponding to 10% input 

signal) of the nominal volume flow. In this case the TRIGGER value should be set to 1000 and the MIN value to 

4000 (6000). 

If zero lapped or slightly underlapped valves are used, the volume flow gain in the zero range (within the underlap) is 

twice as high as in the normal working range. This can lead to vibrations and jittery behaviour. To compensate for 

this, the TRIGGER value should be set to approximately 200 and the MIN value to 100. The gain in the zero point is 

thus halved and a higher overall gain can often be set. 

MIN:A


5.2.30 OFFSET1 / OFFSET2 (Zero correction) 


OFFSET1 X 

OFFSET2 X 

x= -4000… 4000 0,01% STD 

This parameter is entered in 0.01% units. 

The offset value is added to the control element signal at the output. Control element (valve) zero offsets 

can be compensated with this parameter. 

5.2.31 INPOS:S1 / INPOS:S2 (In position window) 


INPOS:S1 X 

INPOS:S2 X 

x= 2… 10000 µm STD 

This parameter is entered in µm. 

The INPOS:S command defines a monitoring window in which the INPOS:S message is displayed. The 

monitoring window is placed centrally on the required position value. The actual position value within this 

window is signalled by the INPOS:S message at the status output (see signal description PROFIBUS). 

The positioning process is not influenced by this message. The control remains active. 

5.2.32 INPOS:D1 / INPOS:D2 (following error window) 


INPOS:D1 X 

INPOS:D2 X 

x= 2… 100000 µm STD 

This parameter is entered in µm. 

The INPOS:D command defines a monitoring window in which the INPOS:D message is displayed. The 

monitoring window is placed centrally on the required position value. The actual position value within this 

window is signalled by the INPOS message at the status output (see signal description PROFIBUS). The 

positioning process is not influenced by this message. The control remains active. 

In NC Mode this message is used to monitor the following error (depending on the parameterisation). 



5.2.33 PROCESS DATA (Monitoring) 

Command Parameters Unit 

WA1/WA2 

W1/W2 

X1/X2 

XD1/XD2 

XK2 

V1/V2 

U1/U2 

Actual command position axis 1 / 2 

External command position axis 1 / 2 

Feedback positon axis 1 / 2 

Control error axis 1 / 2 

Synchronisation error at axis 2 

Speed set point 1 / 2 

Control signal axis 1 / 2 

0,01 mm 

0,01 mm 

0,01 mm 

0,01 mm 

0,01 mm 

0,01 % 

0,01 % 

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


6 Appendix 

6.1 Failure monitoring 


Following possible error sources are monitored continuously: 

Source Fault Characteristic 

Command signal PIN 13 

4... 20 mA 

Feedback signal PIN 14 

4… 20 mA 

SSI-VERSION 

Sensor value 

EEPROM 

(at switching on) 

Out of range or broken wire. The output will be switched off. 



Data error The output is deactivated. 

CAUTION: Take care of the EOUT command. Changes will influense the behaviour. 

6.2 Troubleshooting 

The module can be activated by 

saving new parameters (pressing 

of the SAVE Button). 

It is assumed that the device is in an operable state and there is communication between the module and 

the WPC-300. Furthermore, the valve control parametrisation has been set with the assistance of the 

valve data sheets. 

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

CAUTION: All safety aspects must be thoroughly checked when working with the RC (Remote 

Control) mode. In this mode the module is controlled directly and the machine control 

cannot influence the module. 

FAULT CAUSE / SOLUTION 

ENABLE is active, the 

module does not respond, 

and the READY 

LED is off. 

There is presumably no power supply or the ENABLE signal (PIN 8) or ENABLE signal 

via Profibus is not present. 

If there is no power supply there is also no communication via our operating program. 

If a connection has been made to the WPC-300, then a power supply is also 

available 

If the power supply exists, an attempt should be made to see whether the system 

can be moved by means of the HAND+ and HAND- signals (measuring the output 

signal to the valve helps). 



READY LED is flashing. 

ENABLE is active; the 

READY LED is on, the 

system moves to an 

end position. 


READY LED is on, the 

STATUS LED is not 

flashing, the system 

moves to the target position 

but doesn’t reach 

it (positioning error). 


READY LED is on, and 

the system oscillates on 

the spot. 


The flashing READY LED signals that a fault is been detected by the module. The 

fault could be: 

• A broken cable or no signal at the input (PIN 10/9 or PIN 14/13), if 4… 20 

mA signals are parametrised. 

• Internal data error: press the command/SAVE button to delete the data error. 

The system reloads the DEFAULT data. 

With the WPC-300 operating program the fault can be localised directly via the monitor. 

The control circuit polarity is incorrect. The polarity can be changed with the POL 

command or by reversing the connections to PIN 15 and PIN 16 or 

PIN 19 and PIN 20. 

Serious positioning errors can result from incorrect parametrisation or incorrect system 

design. 

• Is the cylinder position specified correctly? 

• Are the deceleration distances correct (to start the system the deceleration 

distances should be set to approx. 20… 25 % of the cylinder position 9 )? 

• Is the valve a zero lapped control valve or a standard proportional valve? 

In the case of a proportional valve, the valve overlap which may be present 

should be compensated for with the MIN parameters. Typical values are to 

be found in the valve data sheet. 

The system is working and also actuating the valve. 

Various potential problems could be: 

• The parametrisation is not yet adjusted to the system (gain too high). 

• There is severe interference on the power supply. 

• Very long sensor cables (> 40 m) and sensor signal interference. 

• The MIN setting to compensate the valve overlap is too high. 

As a basic principle, the parametrisation of the sensor data and the controller settings 

must be carried out first (before switching on). An incorrect demand is equivalent 

to incorrect system design which then leads to incorrect operation. If the system 

oscillates, the gain should first be reduced (longer deceleration distances for D:A and 

D:B) and in the case of overlapped valves the MIN parameter should also be reduced. 

Speed too low The drive may be able to move to position but the speed is too low. 

• Check the control signal to the valve. 

• Via the integrated oscilloscope (U variable). 

• Measure the signal to the valve with an external oscilloscope / 

voltmeter. 

• If the control is within the range of ± 100% (± 10V), the fault must be sought 

in the hydraulics. 

• If the control signal is relatively low, the following points should be checked: 

• Is the internal/external speed signal limiting the speed? 

• Which setting has been specified for the deceleration distance in 

relation to the POSITION? 

Speed too high The drive should move to position. The drive moves in and out too fast leading to uncontrolled 

behaviour. Reducing the speed (MAX or VELO parameter) has very little 

or no effect. 

• The hydraulic system is over-sized. The entire parametrisation of the 

movement cycle cannot be reproduced (overlap and deceleration distance 

settings) 

9 The stability criterion of the hydraulic axes must be taken into account. 



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. 

i oder I - a 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” 


7 Profibus DP interface 

7.1 Profibus functions 


The module supports all baud rates from 9,6 kbit/s up to 12000 kbit/s with auto detection of the baud rate. 

The functionality is defined in IEC 61158. The Profibus address can be programmed by a terminal program, 

WPC-300 or online via the Profibus. A diagnostic LED indicates the online status. 

7.2 Installation 

A typical screened Profibus plug (D-Sub 9pol with switchable termination) is mandatory. Every Profibus 

segment must be provided with an active bus termination at the beginning and at the end. The termination 

is already integrated in all common Profibus plugs and can be activated by DIL switches. The Profibus 

cable must be screened. PIN 17 have to be connected with PE (low impedance). 

7.3 GSD Configuration File 

The GSD data are available on our homepage: http://www.w-e-st.de/files/software/hms_1810.gsd 

The communication parameters are 16 bytes (8 words) for IN/OUT variables. 



7.4 Description Profibus DP interface 

The resolution (data via Profibus) of the command position is defined in µm (0,001 mm) independent on 

the real sensor resolution. 

The scaled speed is defined by 0x3fff (16373) for 100% of the maximum programmed speed. 

The module will be controlled by the control word, with the following bits: 

• ENABLE1 (2): Must be activated in addition to the hardware signal 

• START1 (2): the new command position is taken over by a signal change from low to high (from 

0 to 1). By deactivation of this bit, the system stops via a programmed deceleration ramp or held 

controlled in target position. 

• HANDA1 (2): Manual mode, speed and direction on internal parameters "HAND1 (2): A". If the 

velocity is limited by the command velocity, only the maximum command velocity can be used 

for movement 

• HANDB1 (2): Manual mode, speed and direction on internal parameters "HAND1 (2): B". If the 

velocity is limited by the command velocity, only the maximum command velocity can be used 

for movement 

• GL: Activation of synchronism, synchronization of axis 2 to axis 1. 

• DIRECT: The target position is directly overtaken (not just on the leading edge of the START 

signal). This bit applies to both axes. 

Command values: 

• Command position1 (2): In positioning mode this is the target position, which is approached 

with "START". 

• Command velocity1 (2): 100 % corresponds to 0x3fff. To traverse the axes a default value 

(even in manual mode) is necessary. 

Feedback of the status words and the actual positions: 

• READY1 (2): System is ready. If the sensor monitoring is enabled, a sensor fault will disable the 

READY signal. 

• INPOS1:S (2): In position window. This bit is used for display only (no effect) 

• INPOS1:D (2): Following error window. This bit is used for display only (no effect) 

• GL-ERROR: the synchronization error is displayed dependent on the parameter "GL: E". This 

bit is used for display only (no effect). 

• Feedback position1 (2): corresponding to the current position in µm (0.001 mm) of the respective 

axis. 


7.5 Commands via PROFIBUS 

7.5.1 Command map 

16 data bytes are sent to the module. 


Nr. Byte Function Remake 

1 0 Control word Hi unsigned int 

2 1 Control word Lo 

3 2 Command position axis 1 Hi Signal resolution independent 

4 3 Command position axis 1 

on the real sensor resolution 

1 µm (0,001 mm) 


6 5 Command position axis 1 Lo 

7 6 Velocity axis 1 Hi Signal range = 0x3fff (16373) 

= 100 % of the nominal speed 

8 7 Velocity axis 1 Lo 

9 8 Command position axis 2 Hi Signal resolution independent 


on the real sensor resolution 

1 µm (0,001 mm) 


12 11 Command position axis 2 Lo 

13 12 Velocity axis 2 Hi Signal range = 0x3fff (16373) 

= 100 % of the nominal speed 

14 13 Velocity axis 2 Lo 

15 14 

16 15 


7.5.2 Definition of the control bits: 

Nr. Bit Function 


Byte 0 – Control word Hi-Byte 

1 0 DIRECT Bit for direct control of the commando position. If this bit is set, 

every change of the command position is taken over as a new 

command position. 

This bit is used for both axes. 

2 1 GL 1: Axis B is synchronized. HANDB2, HANDA2 and START2 

are inactive. 

0: Both axis working independently. 

3 2 HandB1 1: Manual speed B is active. START must be inactive. 

0: OFF 

4 3 HandA1 1: Manual speed A is active. START must be inactive. 

0: OFF 

5 4 - 

6 5 - 

7 6 START1 0: No new command position can be send 

0-1: Signal change from 0 to 1; the new command position is 

taken over. 

1: Positioning mode is active. In case of DIRECT = 1 new 

command positions can be sending continuously. 

1-0: Signal change from 1 to 0; an emergency stop ramp is calculated 

and the positioning process is stopped via this ramp. 

8 7 ENABLE1 1: Axis is active (together with hardware enable) 

0: Axis is inactive, output is OFF. 


1 0 - - 

2 1 - - 

Byte 1 – Control word Lo-Byte 

3 2 HandB2 1: Manual speed B is active. START must be inactive. 

0: OFF 

4 3 HandA2 1: Manual speed A is active. START must be inactive. 

0: OFF 

5 4 - 

6 5 - 

7 6 START2 0: No new command position can be send 

0-1: Signal change from 0 to 1; the new command position is 

taken over. 

1: Positioning mode is active. In case of DIRECT = 1 new 

command positions can be sending continuously. 

1-0: Signal change from 1 to 0; an emergency stop ramp is calculated 

and the positioning process is stopped via this ramp. 

8 7 ENABLE2 1: Axis is active (together with hardware enable) 

0: Axis is inactive, output is OFF. 


7.6 DATA send to PROFIBUS 

7.6.1 Feedback map 

Totally, 16 Bytes will be sent to the Profibus. 


Nr. Byte Function Remark 

1 0 Status word Hi unsigned int 

2 1 Status word Lo 

3 2 Feedback position axis 1 Hi Signal resolution: 

1 µm (0,001 mm) 

4 3 Feedback position axis 1 


6 5 Feedback position axis 1 Lo 

7 6 Feedback position axis 2 Hi Signal resolution: 

1 µm (0,001 mm) 



10 9 Feedback position axis 2 Lo 

11 10 

12 11 

13 12 

14 13 

15 14 

16 15 


7.6.2 Definition of the status bits: 



Byte 0 – Control word Hi-Byte 

1 0 F-Error1 1: No feedback error. 

0: Feedback error in case of a 4… 20 mA sensor. 

2 1 D-Error 1: No Data Error. 

0: An internal data error is detected. 

3 2 - 

4 3 - 

5 4 InPosD1 1: The position of the axis is within the InPosD window. 

0: The position of the Axis is out of the InPosD window. 

6 5 GL-Error 1: No synchronization error is detected. 

0: Axis 2 to axis 1 is not in the synchronization error 

window. 

7 6 InPosS1 1: The position of the axis is within the InPosS window. 

0: The position of the Axis is out of the InPosS window. 

8 7 READY1 1: Axis is working, no error detected. 

0: An error is detected or no Enable signal. 


Byte 1 – Control word Lo-Byte 

1 0 F-Error 1: No feedback error. 

0: Feedback error in case of a 4… 20 mA sensor. 

2 1 - 

3 2 - 

4 3 - 

5 4 InPosD2 1: The position of the axis is within the InPosD window. 

0: The position of the Axis is out of the InPosD window. 

6 5 - 

7 6 InPosS2 1: The position of the axis is within the InPosS window. 

0: The position of the Axis is out of the InPosS window. 

8 7 READY2 1: Axis is working, no error detected. 

0: An error is detected or no Enable signal. 


8 Notes

POS-124-PDP

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