Citect to S7-300 via MPI, is it possible?

[Johnny T]

Hi

I'm working on a project that will eventually involve a PC running Citect talking to some S5 PLC's.

I've got to the stage where I want to test the project but I haven't got any S5 PLC's to test it with so thought I'd hook it up to a S7-312 that I had knocking about.

The protocols available for S7-300 series mention a CP5613 card using MPI.

I don't want to invest in a card just to run a test and wondered if there would be any way of using my programming lead from the com port of the PC to connect to the MPI port on the CPU. The programming lead has obviously got a 232 - MPI adaptor built in to it.

Does anyone know whether it is possible to set up any comms this way or am I just wasting my time. I'm not bothered about speed etc, this is just really to test that my software is transferring everything to the correct place within a Data Block etc.

I've also got a CP340 (RS 232C) card on the test rig so maybe there is an alternative way of connecting the two utilising this??

Anyone any ideas?

Cheers

JT

 

[Doug_Adam]

To communicate with an S7 using MPI, you need to use a CP5613 or similar card. The RS232 and USB adaptors do not work for this function. You also need the Siemens NCM driver software.
I use Ethernet to communicate with S7 plcs.

You could set up the CP340 to talk modbus, and communicate with Citect that way.

Back to your original problem, I would suggest finding an S5 to test it on, since the S5 and S7 PLCs are too different in their communication methods to give a good test. If you get one working, it is un-likely to have much in common with getting the other to work.

 

[Johnny T]

Doug

Many thanks for your reply.

I am interested in how to set up the CP340 to talk ModBus.

I know that its not a true representation by using S7, but I'm fairly confident the S5 comms will work using the AS511 protocol and utilising some RS 232 - TTY adaptors that are already on site.

My project stores a lot of info in datablocks and I'm just wanting to verify that my project is writing to the correct words within the datablocks (and reading correctly as well).

It doesn't matter on the PLC type for this test as all I'm trying to achieve is to test that I'm transferring the correct data from the hard drive database to the correct area within the data block.

Do you (or anyone else) know how I would go about setting up the comms using the CP340 and ModBus. If you could point me in the right direction, that would be great.

Cheers

JT

 

[BobB]

Check the Citect help files for your protocol. Also check the Citect knowledgebase that came with Citect. That is the best reference you can have.

 

[Johnny T]

Bob

I'm looking for info on what Doug mentioned:
"You could set up the CP340 to talk modbus, and communicate with Citect that way."

I need to find out how to set up the CP340 to talk modbus (ie. is this done through Simatic Manager, if so, what parameters need to be set up etc). and how then to get it to talk from Citect.

Cheers

JT

 

[BobB]

I need to find out how to set up the CP340 to talk modbus

Cannot help you with that but the Citect help will indicate how to set up Modbus. Beware, there are several Citect Modbus drivers for slave, master etc, but that is normal. I use the Modbus matsre Citect driver regularly to communicate with fire panels (Wormald) and it works very well.

 

[Johnny T]

Bob

Thanks for the info mate. Will keep an eye out for that.

Cheers

JT

 

[JesperMP]

I have heard from other posters that Citect can connect via CP5611.
The CP5611 is much less expensive than the CP5613, so it might be a better option.
But I dont know the details about how to make the connection from Citect to S7 via CP5611.

 

[BobB]

Here is a link to the Citect driver web page for Siemens.

http://www.citect.com/driverweb/home?cid=418&pid=23920

 

[Johnny T]

Jesper

Thanks for that. I was actually hoping to connect via the CP340 (using Modbus?) as mentioned in one of the previous posts.

Basically I want to avoid (if possible) buying hardware just to test the system.

I've got a 312 PLC, a 313 2-DP PLC, a CP340 card, and SoftNet Lite software...

Ideally what I'm after is some way of getting the citect to talk using any or all of the above.

Any ideas? Is it possible..?

Cheers

JT

 

[Johnny T]

Bob

thanks for the link mate. I've just installed SoftNet Lite on the pooter so I'm going to try that S7NT driver again... although to be honest this is my first venture into the world of OPC's and all the other three letter acronyms that go with it and I'm a bit lost...

Cheers

JT

 

[BobB]

this is my first venture into the world of OPC's and all the other three letter acronyms that go with it and I'm a bit lost...

My last one was BACnet!!!! Do not even want to go there!!!!

 

[Johnny T]

I've just come off the phone to guy from Siemens technical help. He reckons that its impossible to get the system to communicate using the hardware I've got.

He said that the only way to get it talk is to buy a CP 343-1 card (ethernet) and talk via that.

The CP 343-1 card is £1068 !!

Can anyone confirm or deny that this is the ONLY way to get the S7 PLC to talk to my Citect SCADA system as I don't want to shell out all that cash if there is a simpler (and cheaper) way...

Cheers

JT

 

[JesperMP]

Johnny,
you have just experienced the awful help that you can get from Siemens support. Most of the time, the support is excellent, but sometimes you get a dead wrong answer.
If they dont know, they have a tendency to say "it cant be done", in stead of "I dont know".

I am positive that Citect an S7 can connect via MPI and Profibus as well as Ethernet.
If in no other way, Citet can use OPC to make the connection.
But I remember someone discussing to connect directly (I am not 100% sure though).

Obviously, Ethernet is an excellent option, but it may be overkill for some applications.

 

[Johnny T]

Jesper,

The consensus of opinion (from Citect tech and Siemens) is the following...

To connect via the MPI port on the front of the CPU I would require a CP5611 card installed in the PC.

To connect via Ethernet I could use the ethernet port already available on the PC and then buy a CP 343-1 card for the S7 rack.

There are 2 CP 343-1 cards available. One is called Ethernet Lean, but looking at the specs there doesn't seem to be any difference whatsoever except that the lean on is £566 and the normal one is £1068. The normal one takes up 2 slots and the lean one takes up 1 slot..???

I've decided to buy a CP343-1 lean card (it will be here tomorrow) and then try and connect through that.

If that doesn't work I'm going to throw the PC, laptop and S7 rig out of the window, pack up my sandwiches in a red knotted hanky on a stick and live my lifelong dream of becoming a tramp.

Wish me luck....

JT