Free Sensor Sample Order Now

GEL 8251 Compact Controller

Device manual


Table of contents

1       About this document ............................................................................................. 5

2       Safety .................................................................................................................... 7

3       Product identification ............................................................................................ 8

4       Assembly ............................................................................................................. 11

5       Connections ........................................................................................................ 13

6       Commissioning .................................................................................................... 24

7       Technical data ...................................................................................................... 28

1       About this document

1.1       General

The device manual is part of the product and contains the information necessary for installation and for safe operation.

Information on the operation of the device, the system parameters that can be programmed for configuration of the CompactController and the axes controlled, on the PC parameter editor supplied and on the proprietary serial LB2 protocol is contained in the reference manual that is included on the installation CD in electronic form as a PDF file.

Descriptions of any pre-installed PLC program and of the library functions for writing custom programs are not covered here; the comments in the individual function blocks contain appropriate instructions on how to use them.

Please note the following:

  • Carefully read the documents provided prior to the installation and usage of the device.
  • Keep the documentation for the service life of the product.
  • Ensure the necessary documentation is available to the personnel at all times.
  • Pass the documentation on to the subsequent owner or user of the product.
  • Add all supplements provided by the manufacturer of the device.
  • Read and follow the information in the documentation to prevent damage to the product and malfunctions.

This manual is applicable to the standard version of the product. This includes all types that are n o t marked with a Y after the product number in the type code.

A product marked with a Y is a customer-specific version with customised features and/ or modified technical specifications. Depending on the customer-specific modification, further documents or other documents may be applicable.

1.2       Target group

The device manual is aimed at operating companies, machine manufacturers and qualified specialist staff.

Personnel must have adequate knowledge on how to handle components that are sus- ceptible to electrostatic. They must also be familiar with and follow national health and safety regulations.

The operating company must ensure that the safety instructions in this manual are followed and that all individuals tasked with working on the CompactController have read and understood the manual.

1.3       Symbols, marks, notes

The following symbols, marks and notes are used in this document so that you can recognise specific information more quickly:

Dangerous situation: There is a risk of injury on failure to follow the in- structions!
Instructions on preventing damage
Important information for improved understanding, on operation or optimisation of the work processes
Work step to be undertaken

2       Safety

2.1       Safety instructions

The operating software for the CompactController permits on-line changes to system parameters during operation to make it easier to set up the plant and to make service visits easier.

It is imperative on the utilisation of this feature that it is ensured no dangerous situations can arise for individuals in the area of the plant or for the plant itself by

  • Consciously and carefully checking prior to transmission every parameter to be modified for correct application and for the possible effect (above all on changing pitch rates)
  • Ensuring adequate protective measures as well as limit switches and emergen- cy stop buttons are provided.
  • Do not disconnect any connectors or any screen connection with the device switched on to avoid the occurrence of uncontrolled states.
  • Prior to updating the operating system, switch off the power circuits for the drives controlled by the CompactController.

2.2       Designated use

The CompactController is only intended to be used for controlling and regulating drives in the industrial sector.

On operation in residential, business and commercial sectors compliance with the requirements on electromagnetic emissions in accordance EN 61000-6-3 is to be ensured with additional external screening and filtering measures.

The PLC functionality makes it possible to execute customer control programs or control programs supplied using the function implemented in the operating system for controlling drives.

The display and the keyboard make it possible, with appropriate programming, to use the CompactController as an operator terminal for controlling operating states.

The devices are configured using system parameters. This action is undertaken either on the device itself, via the PC editor software BB2100K supplied or via a loaded PLC program.

The data and information given in this manual are to be followed.

3       Product identification

3.1       Scope of supply

  • CompactController GEL 8251
  • Fastening set with 6 nuts, spring washers and washers as well as 2 earthing terminals (order no. BG 4623)
  • Mating connector set (order no. GEL 89042
  • Cable clip set (order no. BG 4622)
  • Installation CD with the following content (can vary):

–    Operating system file in the latest version (for download to the CompactController), electronic
     documentation (PDF) and configuration files

–    Update software LingiMon

–    CoDeSys (PLC programming environment)

  • Setup
  • Libraries
  • Documentation (PDF files in various languages)

–    Acrobat Reader for reading the PDF files supplied (self-extracting installation program)

The CD has an autorun program that provides information and various possible options in a dialog box after the insertion of the CD, provided the autorun function is activated on the PC. If the CD does not start automatically, you can start the installation manually by running the program start.exe in the root folder on the CD.

  • Optional: Cable terminals for horizontal cable outlet (without separate attachment frame)

3.2       Rating plate

The rating plate is bonded to the side on the connection frame.


1 Type (order) code

2 Serial number

3 Nominal operating voltage

3.3       Parts named

3.3.1      Front panel

front panel

1      Display

2      Function keys (assignment dependent on the current window)

3      Numerical keys (value entry)

4      Enter key: Confirm entry, select/open entry marked (identical to 7)

5      Escape key: Cancel entry/function; return to next menu level up

6      Navigation and selection keys (select property of a system parameter)

7      as for 4

8      Scroll keys (move up/down by one line the window in the overall list that can be displayed)

9      Delete key: Delete value entry

10    Menu keys (assignment dependent on the actual window, row orientated)

3.3.2      Display

The function of the display is dependent on the CompactController operating system and any software expansions loaded. There is a corresponding description in the reference manual.

3.3.3      Rear side

rear side

1      Front panel

2      Connection frame

3      Cover with attachment frame mounted (cable clips for vertical cable outlet) and cut-out for optional field
        bus module (3a)

4      Encoder connections (terminal strips Z1–3)

5      DIP switch for CAN bus termination

6      CAN bus connection (terminal strip C2)

7      Connection analogue inputs U/I (terminal strip E6)

8      Connection analogue inputs PT100 (terminal strip E5)

9      Connection digital inputs and LED status indicators (terminal strip E4)

10    Connection power supply (terminal strip V)

11    DIP switch for terminating RS 422/485

12    Connection serial interfaces RS 232/422/485 (connector C1)

13    Connection digital and analogue outputs and LED status indicators (terminal strips A1–3)

14    Connection digital inputs and LED status indicators (terminal strip E1–3)

15    Studs for control panel mounting

4      Assembly

4.1      Installation

Control panel cut-out

Control panel cut-out
  • Make the necessary control panel cut-out and fastening bores in the required po- sition in the switch cabinet.
  • Insert the device in the control panel.
  • Fasten the device using 6 nuts M4, spring washers and washers.
  • Make the electrical connections taking into account the information in section 5.
  • Fit the cover and fasten the 4 knurled screws.
  • Fix the cable to the connection frame and to the cover itself with the aid of the clamps.

4.2      Removal

  • For brief removal of the CompactController undo the four knurled screws in the cover (are captive in the cover) and disconnect all connectors.

   After refitting the cover first press on the knurled screws and then tighten them.

  • Remove the 6 nuts on the M4 studs on the CompactController and remove the device

4.3 Module installation

The CompactController can be upgraded at a later date with a function module (field bus). The installation, the connections and other information on the module are described in a separate document (also on the CD supplied in electronic form).

   Ensure that all pins on the module edge connectors are sitting correctly in the related housing

Communication with the extension modules is via a PLC program using CoDeSys function blocks provided. The basic configuration is undertaken using various system parameters (→reference manual).

5      Connections

5.1      Information on wiring

To improve the electromagnetic environment (EMC) please follow the following installation instructions:

  • Correctly earth device: Short connections via cable lug contacts (6.3 mm) housing/ cover → switch
       cabinet (wall) as well as between housing/cover (use low inductance earth strap or flat conductor)
  • Earth connector cable at the device: Strip insulation from cable screen at a suitable point and clamp
       under a cable clip on the cover (see figure)information with wiring
  • Use metal D-Sub mating connector and
       clamp the cable screen cleanly between
       the halves of theconnector
  • Tighten fastening screws for the D-Sub
       mating connector to ensure a reliable earth
       contact (however it is recommended to
       additionally earth this cable as show in the figure)
  • For good electrical contact and mechanical restraint of the cable in the terminals as well as for reliable
       isolation, fit the cable cores used with insulated ferrules in accordance with DIN 46228 Part 4 that are
       permanently connected to the cores with the aid of a special crimping tool. If two or more thinner cables
       are to be connected to a terminal, the usage of twin ferrules is advantageous. The maximum connection
       cross-section is 1.5 mm2 (incl. bush).
  • To tighten the terminal screws (M2) use a screwdriver with a 0.4x2.5 mm blade.

  • Keep all unscreened cables as short as possible
  • Attach screens at both ends of cables using a connection with as large a surface area as possible
  • Ensure that external protection measures against surges have been implemented (EN 61000-4-5).
  • In case of inductive loads (relays, contactors) on the digital outputs, provide suppression measures (free-
       wheeling diode or RC element in parallel and in the immediate vicinity of the coil)
  • Lay signal cables and control cables physically separate from power cables
  • If there are potential differences between the earth connections for the machine and electronics, or if
       such differences occur, ensure by means of appropriate measures that no equalising currents can flow
       via the cable screen; (e.g. lay an equipotential bonding cable with a large cross-section or use cables
       with a separate double screen with each screen connected at only one end.)

   Do not disconnect any connectors or any screen connection while the device is switched on.

5.2      Connector coding

connector coding

5.3      Overview


5.4      Power supply V

   Both the power for the internal circuits in the CompactController (UB) and the power for the
   supply of encoders connected (UZ) is provided at terminal strip V.

Power supply V

   If only a single power source is used to supply the controller and encoders, the related terminals
   3 and 4 as well as 1 and 2 must be connected together as shown dotted in the figure.

5.5      Serial interfaces C1

   Two independent serial interfaces are available on connector C1: COM 1 and COM 2.

COM 2 is designed as pure RS 232 C.

COM 1 can be used either as RS 232 C or as RS 422/485.

The serial interfaces have the same earth potential as the CAN buses (connector C2).

In the case of RS 422/485 the internal termination resistors must be enabled on the
first and last device on the bus using the DIP switch beside the connector: both
switches in the ON position. The resulting termination resistance is approx. 125 Ώ

Serial interfaces C1

   On the usage of RS 485, the connections 6 and 7 as well as 8 and 9 must be connected using solder
   jumpers (shown dotted in the figure).

5.6      CAN bus C2

   Two CAN bus interfaces are available on terminal strip C2: CAN1 and CAN2.

The internal termination resistor for the specific CAN bus must be enabled
on the first and last device on the bus using the DIP switch beside the
connector: Switch in ON position. The terminating resistance is approx.
120 Ώ

The CAN buses have the same earth potential as the other serial interfaces (connector C1).

CAN bus C2

5.7      Encoder inputs Z1–3

   2 SSI encoders can be connected to each of the terminal strips Z1 to Z3 .

5 V and 24 V are output there as the operating voltage for the encoders (provided at terminal strip V). The maximum currents are

  • At 24 V: 300 mA per encoder
  • At 5 V: 200 mA per encoder, in total 0.6 A

All encoder inputs have the same earth potential.

Encoder inputs Z1

5.8      Digital inputs E1–4

    The signal state on the 6 (E1) or 8 (E2 to E4) digital inputs is indicated by green light emitting
    diodes underneath the related terminal (on = high).

Digital inputs E1

5.9      Analogue inputs E6

    The analogue inputs can be set for the measurement of
     – currents 0 – 20 mA or
                         – voltages 0 – 10 V.
                         A jumper is provided for this purpose beside the terminal strip for each of the max. 3 inputs.

Standard configuration: Current measurement (I)

For voltage measurement (U) fit the related jumper. For this purpose the
cover with the cable clips must be removed: Undo 4 knurled

The measuring ranges are converted internally to a value range from 0...255 (1 byte).

Analogue inputs E6

5.10      PT100 analogue inputs E5

    These 4 special analogue inputs are provided for temperature measurements using PT100
    resistors in the range from -40 °C to +215 °C.

The measuring range is converted internally to a digital value range from 0 to 255 (1 byte).

The measuring range is converted internally to a digital value range from 0 to 255 (1 byte).

PT100 analogue inputs E5

5.11      Digital and analogue outputs A1–3

    Each of the 3 output terminal strips A contains:
     – 3 digital outputs 30 mA (terminals 5, 6, 7)
                                        – 2 digital outputs 500 mA (terminals 8, 9)
                                        – 1 analogue output for the axis control (terminals 2 + 3)

The digital outputs on a terminal strip each have a separate earth potential. The minus connections for the analogue outputs are connected together.

The signal state on the digital outputs is indicated by red light emitting diodes under- neath the related terminal (on = high).



6      Commissioning

6.1      CompactController

After switching on and a short initialisation process, specific changes can be made to the CompactController and the axes to be controlled using the system parameters de- scribed in the reference manual.

After setting all axis-related control parameters, the drives can be moved manually us- ing the keyboard on the Controller.

6.2      Operating system update

   Prior to updating the operating system, switch off the power circuits for the drives controlled by
   the CompactController.

If new operating system software is to be installed on the CompactController (e.g. available on the Internet at, use the tool provided for this purpose

  • To install LingiMon, start the program LingiMonSetup.exe on the CD or simply click the related menu command in the CD autorun program.

The application will now be installed in the usual manner for Windows (it is possible to change the folders to suit specific needs).

   If LingiMon has already been installed, the previous version will first be uninstalled by the
   installation routine:

Operating system update Confirm uninstall
                "Do you really want to remove the selected application and all its components?"

LingiMonSetup must then be started again for a new installation.

  • After installation start the program either via the Windows Start menu or by using the left mouse button to double-click a binary file with the extension '.h86' or '.b86' in Windows-Explorer.
  • Using a null modem cable establish a connection between the PC (RS 232 C: COM1/2) and the CompactController (connector C1).
  • In the program select the COM port used (to be set via the connector icon).

   The transmission rate is set to 57,600 baud by default. If problems occur during the data transfer, first
   the transmission rate should be reduced in steps to the minimum value of 9,600 baud (to be set
        via the connector icon).

        Other communication parameters: 8 data bits, even parity, 1 stop bit, no control

Starting LingiMon with selected binary file (.h86)

binary file

   The status bar provides information on the COM port (COM 2) selected, the transmission rate (57600
   Baud) as well as type of file loaded.

Prior to transmitting the data to the flash memory on the device, this memory is first cleared. In general it is sufficient to clear only the operating system area as per the default in the program. Then any existing PLC program and the system parameter settings will be retained. The other option can be enabled in the Download options (click connector icon).

   Do not switch to another application during the transmission of the data – the transmission window must
   remain active, progress can then be followed using the progress bar displayed. Otherwise Windows-
        specific errors can occur during the transmission process that will result in the CompactController
        ceasing to respond. In such a case repeat the transmission.

After confirming using OK, the program will prompt you to reset the device.

binary file
  • Switch off the CompactController.
  • Press the miniature button in the housing as per the following figure using a non-metallic object (e.g. match) and switch the device back on.
binary file
  • Release the button again.
    The CompactController is now ready for the download (only one or more lines can be seen on the display).

After confirming using OK the transmission process starts (approx. 250 Kbytes for "op- erating system"):

binary file

At the end of the (successful) transmission the CompactController switches to normal operation. If not, repeat the transmission process possibly with a reduced transmission rate.

The contents of the complete flash memory or only parts of the memory can also be uploaded i.e. read and saved in a file with the extension '.b86'. This file can be written back again at any time – as explained above (backup function). The name of the file is generated automatically by the option selected, but can be changed if necessary.

binary file

The memory area to be uploaded is defined using the
Upload options (click connector icon).

Using the magnifying glass icon a comparisoncan be
made between the data displayed and the data in the
CompactController. A corresponding upload process is
started for this purpose.

7      Technical data

7.1      Specifications

Electrical data
Supply voltage VS 19 to 30 V DC
Power consumption 1 A max. (depending on interface)
Serial RS 232 2 (COM1/2), adjustable baud rate, for PC
COM1: RS 232 C
COM2: RS 232 C or RS 422/485
CAN bus 2 x onboard (master / slave)
Field bus 1 extension slot for PROFIBUS DP, Inter-
Bus-S or DeviceNet (others on request)
Counting inputs 6 x absolute SSI, power supply 24/5 V,
900/600 mA in total, clock frequency
125 kHz
Digital inputs (galvanically separated) 30 x 24 V, green LED status indicators
Analogue inputs (galvanically separated) 3 x selectable alternatively 0 to 10 V or 0
to 20 mA
PT100 inputs (galvanically separated) 4, -40 °C to +215 °C
Digital outputs (galvanically separated) 9 x 24 V, 30 mA
6 x 24 V, 500 mA
red LED status indicators
Analogue outputs (galvanically separated) 3 x ±10 V, max. 10 mA, 2 mV resolution
Memory programme: 256 KByte
data: 128 KByte
data backup: 128 KByte
NV RAM: 4 KByte
Programming according to IEC 61131-3, CoDeSys environment
Ambient data
Protection class front side: IP 65, rear side: IP 20
Operating temperature -20 °C to +70 °C
Storage temperature -30 °C to +70 °C
Relative humidity of air 95 %, non-condensing
Vibration resistance (IEC 60068, 2-6) 20 m/s2, 9 to 50 Hz
EMC EN 61000-6-2 and 4(1)
Display LCD 64x240 px with LED backlighting; visible area 133 x 39 mm
Material galvanized sheet steel
Front panel edge-protected aluminium
Weight approx.1.7 kg

7.2 Dimensional drawing (Figures in mm)


dimensional drawing

With horizontal cable outlet (option

dimensional drawing