Control Valve through Analog Input/Output - Beckhoff PLC

tech007
2011-05-10
2018-06-08
  • tech007 - 2011-05-10

    Hello,

    I would like to control the valve (MXG461B15-1.5)through the beckhoff PLC. The valve operating range is from 0-10 volts and i have terminal EK 1100 (EtherCAT communication terminal), EL 3162 (Analog Input terminal)and EL 4104 (Analog Output terminal).

    Can you suggest me how to control the valve through analog input and output terminal ?

    How to programme analog input and output terminal ?

    Thanks.

     
  • Rolf-Geisler - 2011-05-10

    Hi,
    to configure and run a Beckhoff PLC you need to go a few simple steps:
    1. Write the PLC program. Declare the inputs / outputs in a configurable way, e.g. "ValveOutput AT %Q*: WORD;"
    2. Open the TwinCAT SystemManager, use the Actions menu to set it to Configuration mode
    2a. Make a new TwinCAT SystemManager project, add an EtherCAT device to the I/O configuration --> I/O Devices (see Beckhoff documentation for details of driver and protocol installation), then scan the boxes.
    2b. In the TwinCAT SystemManager PLC-Configuration, add your PLC project.
    2c. Then, in the TwinCAT Systemmanager I/O list, expand the terms to the used inputs / outputs. Click a term and use the "Linked to ..." button to assign this terminal to an input/output variable of the PLC program.
    2d. When all used inputs/outputs are assigned to the matching PLC input/output, use "Actions --> Activate Configuration" to activate this configuration (this also will set logical input/output addresses in PLC program) and to switch over to Run Mode.
    3. Go back to PLC program, go online (this will download the PLC program).

    http://www.geisler-controls.de there is the freeware library AnalogEA.lib, which has some useful procedures to handle analog signals (unfortunately, documentation is in German only).

    I don't know the MXG valve, so I do not have any advices how to control it. Maybe, somebody else can help.

    Have success
    Rolf

     
  • tech007 - 2011-05-11

    Hi Rolf,

    Thanks a lots for your detailed answer.
    I will go through step by step.
    And then develop some code. For valve controlling, i will try to find it out from
    siemens documentation.
    I will check it your documentation. I can understand basic german. So, no problem.
    Once again thanks.

     
  • alfi - 2011-05-12

    Hi Tech007,

    My idea about handle the simulation of analog input/output. First you must make a simple function to handle signal conversion (0..10V) into digital value and vise versa. Once, you're already make the function block, you could use analog signal (example potentiometer) to generate input value. And base on this value you could translate it to be analog "valve open stroke".

    It nice to handle analog I/O through Beckhoff EK1100 and use your PC as PLC. Don't forget to create bootfile so you may handle it without your PC.

    Thanks...

     
  • shooter - 2011-05-16

    you can not use both signals as the valve has a small dipswitch to set it OR to Voltage (both input and output or to current.
    There is a way with a small resistor of 1 Watt (however you will not need the feedback so go with your current output as this can have long distance.

     
  • tech007 - 2011-05-23

    Hello,

    I using beckhoff terminal EK1100,EL3162(analog input) and EL4104(analog output). The application is to control the valve thorugh analog input and output terminal. But right now, i want to programme analog terminals.

    I am giving additional 10 V DC to analog output terminal and measuring at analog input terminal through multimeter.

    I would like to have similar voltage 10 V DC at input terminal which i am giving at analog output terminal 10V DC.

    My problem is at analog input terminal i am getting variable DC voltage although i am giving contast dc voltage to analog output

    terminal. And this varibale voltage is keep decreasing and reachign zero at analog input terminal which i want to measure.

    There is no error as well. All terminals in OP mode.

    For programme, i am using FB which is analog_in and analog_output and variables linked through respective input and output.

    Can somebody help me with this ?

    Can i have example programme for Twin CAT system ?

    Thanks.

     
  • shooter - 2011-05-23

    this is a crosspost.

    open the cover of the valve
    use a screwdriver and it will initiate automatic.

    you can not measure current with a voltagemeter as the input will always be zero (inside the input is not a simple resistor but the current is measured by another current coming from the opamp.

     
  • awaisyaqoob - 2018-06-08

    hello. can you please help me out with connecting Beckhoff plc using Codesys.

     

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