Experimental Physics and
Industrial Control System

Konrad Gajewski <[email protected]> · Fri, 23 Mar 2012 12:59:03 +0100

Hi Jens,

Thank you for your update. Can you give me some details - was it a Step 7 program that you had to change or have you got a patch from Siemens?

Btw, I'm trying to connect S7-200 PLC via serial line using asyn Modbus driver and Siemens Modbus library. So far it's not working (the communication works fine, I get the error message from the slave, so I hope I can fix it soon). 

Best regards,
Konrad. 

23 mar 2012 kl. 12:12 skrev Rekow Jens <[email protected]>:

> This topic is a few weeks old already but for your information, sometimes 'All is well that ends well':
> 
> Our connection handling problem is solved after some help of the Siemens support. Interfacing with the SLS S7 driver to a Siemens PLC directly connecting to a CPU315-2 PN/DP works fine now.
> 
> The problem we had was a timing issue. Most likely the PLC tried to initialize functions to quickly after booting. That made the TCON function got locked sometimes.
> 
> HTH,
> Jens
> 
> 
> 
>> -----Ursprüngliche Nachricht-----
>> Von: [email protected] [mailto:tech-talk-
>> [email protected]] Im Auftrag von Rod Nussbaumer
>> Gesendet: Mittwoch, 22. Februar 2012 18:20
>> An: Konrad Gajewski
>> Cc: [email protected]
>> Betreff: Re: Connection to Siemens S7 PLC
>> 
>> At TRIUMF, we are using our own driver to talk to 400-series Siemens
>> PLCs. It uses asyn, and was modeled after Mark Rivers' modbus PLC
>> driver. The underlying communications protocol is the Siemens
>> FETCH/WRITE protocol over TCP/IP.
>> 
>> Rod Nussbaumer
>> ISAC Controls, TRIUMF
>> Vancouver, Canada
>> 
>> 
>> Konrad Gajewski wrote:
>>> Hello everybody,
>>> 
>>> I'm new to EPICS and I am planning to control Siemens Simatic S7-200
>>> PLC. I have looked in EPIC documentation and found at least two ways
>> to
>>> connect the PLC:
>>> 
>>> 1. via MODBUS (Asyn) driver over the serial connection (using Siemens
>>> MODBUS RTU library)
>>> 2. using S7plc driver via TCP/IP and a CP 243-1 Ethernet module.
>>> 
>>> The programming of the PLC is done using Step-7 Micro/WIN V4.0.
>>> Unfortunately I can't open the example STEP 7 PLC project (for S7plc
>>> driver) in Step-7 Micro/WIN.
>>> 
>>> Do you have any experience with such a configuration or maybe with
>>> S7-1200? Are there any better options?
>>> 
>>> Thanks,
>>> Konrad
>>> 
> 
> 
> 

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System