Re: Communication between EPICS and PLCs at your facility?

[Torsten Bögershausen via Tech-talk <tech-talk at aps.anl.gov>]

Hej Ayaz,
that is a good question. What we use and we recommend?

What is in use ?

For PLC-ish applications Modbus/TCP (I think it's called) is usesd.
There is a tool generating both PLC code and EPICS "databases" are generated based on a .def file.

For Motion Control with some additional IO and timestamping inside the PLC
we use a protocol based on ADS.
This solution is based on the model 3 motor driver, and there are too many details to be described here.

For more data-aqcuisition-heavy applications we have the epics-twincat-ads module,
which allows transfer of arrays and all other types of EPICS Records supported by asyn.

For Sample Environment Equipment, which is moved between beamlines and 
even research institutes there is the Secop initiative:
https://github.com/SampleEnvironment/SECoP
 
Where the "EPICS Records" are provided by "octopy", but I am not an expert here.

And of course UPC-UA can be used - not my area of competence either.

So all in all, it depends how complex your PLC code is, requirements on data rates,
timestamping, slow control, medium slow control and faster controls.

This is all my personal view, which may be incomplete.

 HTH
/Torsten



On 2022-07-06, 13:05, "Tech-talk on behalf of Samadli, Ayaz via Tech-talk" <tech-talk-bounces at aps.anl.gov on behalf of tech-talk at aps.anl.gov> wrote:

    Dear All,
    
    At the European XFEL, we have an R&D project to replace the current custom communication protocol between our in-house SCADA system, Karabo, and PLCs (Beckhoff). I would be interested in your recommendations and current implementations for communications between EPICS (or other SCADA systems) and PLCs at your facility. Can you please share your experiences and suggestions with us? 
    
    If you want to get more details, please feel free to reach out to me. 
    
    Best Regards,
    Ayaz
    
    
    Ayaz Samadli
    
    Controls - Control Software Engineer
    
    
    European XFEL GmbH
    
    ayaz.samadli at xfel.eu
    
    www.xfel.eu
    
    
    Headquarters: Holzkoppel 4, 22869 Schenefeld, Germany
    
    
    Managing Directors: Prof. Dr. Robert Feidenhans’l, Dr. Nicole Elleuche
    
    Registered as European X-Ray Free-Electron Laser Facility GmbH at
    
    Amtsgericht Hamburg, HRB 111165