Re: Siemen's PLC Interfaces

[Luedeke Andreas <andreas.luedeke@psi.ch>]

> Could you describe in more details you setup?
>  

Hi Emmanuel,
you just need an Ethernet module for the S7.
All the libraries for the S7 PLC side are provided with the Step7 
software, the one you need anyway to program the PLC.

You specify a data block for reading and one for writing.
The communication is via Tcp/IP sockets.
The S7PLC driver just opens the socket to the PLC and maps the data 
blocks on the IOC to EPICS channels.
The same socket protocol is used for inter-PLC communication, too.

We use VME CPUs with a second Ethernet interface (mv5100) as IOC and 
keep the PLC network separated from the slow control network.

The set-up runs very reliably at PSI and it is used for many systems 
(Machine Interlock System, Equipment Protection System, Vacuum Control 
System, Insertion Device Control, ...)


Dirk already mentioned the link http://epics.web.psi.ch/software/s7plc

In addition I found an old document in German for the PLC programming 
http://people.web.psi.ch/luedeke/public/TM-93-00-04.pdf
It contains examples how to set-up the PLC.
I'll ask our PLC developer if there's more or newer documentation.

I hope this helps for a start.

Regards
Andreas


Emmanuel Mayssat wrote:

> Andreas,
> You are mentioning that you have no special hardware or proprietary
> software. Are you sure? Recently I investigated several ways to
> communicate with the PLC. I even met with Siemens sales reps.
>
> As far as I know write access requires 
> 1/ Modbus card 
> 2/ and/or Proprietary libraries/interface software
>
> Could you describe in more details you setup?
>
> Thanks,
> --
> Emmanuel
>
> On Fri, 2006-11-10 at 18:40 +0100, Luedeke Andreas wrote:
>  
>
> > The s7plc driver is used for the Linacs of Diamond (VME IOC) and ASP (PC 
> > IOC), too.
> > In both cases read and write access of about 10Hz of a few hundred PVs 
> > per PLC.
> > No problems reported so far.
> >
> > No special hardware or proprietary software required.
> >
> > Andreas
> >    


--
Dr. Andreas Luedeke, SLS Operations Manager, Tel:+41-56-3104002
mailto:Andreas.Luedeke@psi.ch, http://people.web.psi.ch/luedeke