direct communication with SIEMENS PLC

[sdoctor]

I am trying to establish a direct connection with a SIEMENS S7 PLC. I donot want to use any card or profibus etc. I want to do it through the Serial Port.
I have used the IA server kit when communicating with SIEMENS S5 for which I used AS511 protocol. I would like to know if there is any such protocol for S7.

Please Help!!

[mrak1]

Hi,

This is hard to answer because it all depends on whether or not the SIEMENS S7 PLC can communicate using a the AS511 protocol. This protocol is supported by National Instruments Industrial Automation OPC Servers. However it doesn't state any specifics about the S7 PLC. You may want to check with SIEMENS for a serial OPC driver which you could use with LabVIEW.

The list of supported PLC and Protocols are listed here:

Where can I Find Drivers for Communicating to PLCs, RTUs, and Other Industrial Hardware? 

Here is information about using OPC with LabVIEW:
Connecting LabVIEW to an OPC Server through a DataSocket Connection

Good luck,
Mike

[sdoctor]

Hi Mike,

Thanks for your answer. But what I want to know is whether there is a OPC driver which I can use. I have tried contacting SIEMENS, but I have not received any answer from them.

Also I dont necessarily need to use AS511. I quoted that only as an example.

[Rumcajs]

Hi.
I'll try explain it.
All Simatic S5 PLc's processors (CPU90 ,CPU100) have got serial (current loop converted to RS232) physical inteface as standard.
You can program PLC's or communicate with its by AS511 protocol.
S7 Simatics processors (CPU 3xx, CPU4xx) haven't got RS232 interface as standard. RS 232 interface occurs in forms of interface module connected to the rail (slot) and doesn't serve any protocol (simple chracters exchange).
You can program PLC, observe/modify I/O, variables, etc. only by standard RS485 interface using protocols MPI or PROFIBUS (PPI/MPI for Simatic S7-2xx CPU's).
You can try exchange data between Labview and S7 PLC by serial in characters form, but it is very difficult and inconvenient (you have to w
rite own driver for Labview and program for S7).
Another solutions:
1.PROFIBUS card for PC with drivers for Labview (I don't know if they exist)
2.connection thru OPC server (PLC->PC by PROFIBUS card->OPC server->Labview by Datasocket)
I think second solution is more comfortable.
See also:
Connecting LabVIEW to an OPC Server through a DataSocket Connection
Regards.
Romek.

[jag]

This is not an answer but a question for the originator. I am trying to us the IA Server kit to communicate with a Siemens S5 using AS511 protocol, but with no luck. I'm using a cable and a current loop converter that works with the S5 programming software. Any suggestions would be appreciated.

[RZEIDE]

Dear Sir,

I have read Your answer on the web (ni.com site: http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=50650000000800000050430000&ECategory=LabVIEW.LabVIEW+General) to a question towards connecting a siemens PLC S5 via RS232 to a PC with LabView.
In our Lab we use a Simatic S5 (928CPU U135) which I want to connect via serial port (COM0..1).
My question is:
Is this AS511 protocoll part of the LabView (I use V6.0) application, available softwaretool from Siemens or can I download it somewhere?
Do I need that protocoll for simple data reading and writing?
In LabView one have to use VISA -> Instrument -> OPC ... where can I find the how the orders have to look like (read, write... a special Datablock
, Memoryblock...)

Thanks a lot in advance for Your friendly help,
Yors sincerely,
Ralf Zeides