Siemens communication with Rockwell

Hello!

We are trying to do an upgrade on a clients system. It was built about 20 years ago and the current communication setup is Siemens PLC (CPU314C-2 DP) -> Citect Scada 5.42 -> 1394 GMC Turbo which was programmed with GML Commander. The servo system gets its information from Citect system and the PLC doesn't communicate directly to the servo system.

Now we are trying to eliminate the Citect Scada system from the equation and add a Siemens TP1200Comfort and the PLC must communicate directly to the servo system.

What i could gather from the Citect system is that it sends/receives about 20 INT data types most of them are recipe parameters with the 1349 GMC Turbo
It seems that the communication is currently being done with the servo system through DH485 in the J1 port.

What i am trying to figure out how to get the PLC and servo system talking the same language without messing with the 1394 GMC Turbo and GML Commander too much.
I found the DH485 pinout for the servo system from the manual (attached to the post) So i guess that should be the servo side cable pinout?

Could someone please give me some clues or direction what would be the move to get the Siemens PLC and Rockwell Servo system communicating with each other?

I've never done it but according to Siemens it can be done with a CP341

https://cache.industry.siemens.com/dl/files/110/1218110/att_35773/v1/DataHi_e.pdf

The TP1200 is an HMI, what PLC are you planning to use?


I think the manual Cottagewood refered to is for a driver (you have to purchase) for the 300/400 series in Simatic Manager. I can only imaging how hard this will be to get to work (not to mention the price..)



Not familiar with the data highway, but maybe it would be easier to use a gateway/converter.

boneless said:

The TP1200 is an HMI, what PLC are you planning to use?


I think the manual Cottagewood refered to is for a driver (you have to purchase) for the 300/400 series in Simatic Manager. I can only imaging how hard this will be to get to work (not to mention the price..)



Not familiar with the data highway, but maybe it would be easier to use a gateway/converter.

Click to expand...

Edit
I'd assumed keeping the S7-300 was being kept,


I'm not sure an MPI/DH gateway exists which would mean modbus on the S7300 which is also costly

boneless said:

The TP1200 is an HMI, what PLC are you planning to use?


I think the manual Cottagewood refered to is for a driver (you have to purchase) for the 300/400 series in Simatic Manager. I can only imaging how hard this will be to get to work (not to mention the price..)



Not familiar with the data highway, but maybe it would be easier to use a gateway/converter.

Click to expand...

I am planning to use the same main PLC that is currently in the system already CPU314C-2 DP

True, I missed the PLC specced in the first post.


Profibus might be a solution.

boneless said:

True, I missed the PLC specced in the first post.


Profibus might be a solution.

Click to expand...

Yep, that would also work through a gateway

boneless said:

True, I missed the PLC specced in the first post.


Profibus might be a solution.

Click to expand...

So something along the lines of Profibus to DH485 converter/gateway?
Or a Profibus to RS232 converter/gateway? Or something else?

To be honest, all of these number and letter combinations (RS232, RS485, DH485 etc...) are a complete blur for me.

I guess since currently the DH485 is in use, then Profibus to DH485 but i could only find products that are disconnected and were meant for a Profibus slave

Profibus to DH485. Yikes !
This company made a gateway:
https://www.prosoft-technology.com/Products/Gateways/DH-485/DH-485-to-PROFIBUS-DP-Slave-Gateway
But notice that it has been discontinued.
Avoid DH485 !!

The S7 314C-2DP is also not exactly new any longer.

In my opinion, take a deep breath and ditch all this legacy stuff. I would go for new PLC and a new servo that talks natively with each other over an uptodate protocol, i.e. Profinet not Profibus and definitely not DH485.

If that is too drastic for you, get a new servo that connects as a DP slave to the 314C-2DP.

JesperMP said:

Profibus to DH485. Yikes !
This company made a gateway:
https://www.prosoft-technology.com/Products/Gateways/DH-485/DH-485-to-PROFIBUS-DP-Slave-Gateway
But notice that it has been discontinued.
Avoid DH485 !!

The S7 314C-2DP is also not exactly new any longer.

In my opinion, take a deep breath and ditch all this legacy stuff. I would go for new PLC and a new servo that talks natively with each other over an uptodate protocol, i.e. Profinet not Profibus and definitely not DH485.

If that is too drastic for you, get a new servo that connects as a DP slave to the 314C-2DP.

Click to expand...

As i said, the system was built about 20 years ago.
It would be nice to use more modern components but it is the clients wallet and they are calling the shots. Ofcourse if everything else fails and there is no light at the end of the tunnel then the client will have to decide what they would rather want to do.

But to go back to the topic..
The manual says that the servo system can also use RS232 and RS422 aswell. But since i have not actually tested it in real life is only a theory.

A quick google shows that Profibus to RS232 is a much more common conversion. And there are a couple of options.

What do you think, would Profibus to RS232 work?

Also if I use Profibus to RS232 is it just a matter of PUT/GET blocks or how would the data transfer work out?

PUT/GET is used with socalled "S7 connections" which is a proprietary method used by Siemens only.

Is there anything special about this servo ?
The most direct way and for which you may find manuals, application examples, and also get support and spare parts in the future is a servo that is a DP slave for the 314C-2DP.
Anything with gateways etc. will also be expensive, and you will more or less be on your own on how to get it to work. If I was the customer I would not accept a cludge as a solution.

You should avoid the DH 485 like the plague! I was unreliable at best.
What I used to do was install flex I/O modules and send discrete bits to and from the 1394 system to the plc based upon the the part number the operator selected. The servo would run the program and then report back to the PLC when complete. This was the most reliable way to communicate to the 1394 system. You have a control system that has been obsolete for many years. Your customer needs to understand the risks involved with this "fix". Take JesperMP's advice and upgrade the PLC and hardware. You might be able to salvage the motors if you stay with an AB solution. Then again, it might be cheaper to upgrade to a complete Siemens solution if that is what you support.

Alright, new plan.
I found out that there is a Rockwell 1769-L31 PLC in the electrical cabinet as well which is inspecting faults with the product etc.

I have had time to look out what data are we exactly exchanging between the 1394 GMC Turbo system and the Citect Scada. Basically we are sending a couple of recipe values to the Servo and receiving actual speed and length count from the Servo.

I have seen that the Rockwell PLCs have been used with Siemens HMIs
(See attachment: Rockwell Communication)

I have an idea to perhaps connect the S7-300 PLCs and the 1769-L31 PLC to the HMI and the 1394 GMC Turbo with the 1769-L31 PLC.
So if an operator inserts recipe data to HMI, we send the recipe data first to the 1769-L31 PLC and from there to 1394 GMC Turbo and vice versa, if the machine is in auto mode, we get actual speed from 1394 GMC Turbo which sends it to 1769-L31 which sends it to HMI.
(See attachment: Connection diagram)

Would it work?

The only problem i can think of is that the 1769-L31 only has RS232 DB9 ports for communication. So do i need to make a special cable between TP1200 Comfort LAN/Profinet port and 1769-L31 RS232 DB9 port?


Thanks!

You need to first find out exactly how the 1769-L31 communicate with the GMC drives.
The 1769-L31 has 2 serial ports. Are they already in use ?
A problem could be that one port already communicate with the drives, and another port communicate with an HMI, so there are no free ports to connect the TP1500 to.

If there is actually an unused serial port on the 1769-L31, then you are in luck since the TP1500 can talk DF1 natively.
You may have to setup the tags that the TP1500 uses as PLC5 style variables.
And you may have to add an RS485/RS232 converter since the port on the TP1500 is RS485 only.

Whoops, hang on.
The S7-300 is a 314C-2DP ? If so, there is no ethernet for the TP1500 to connect to.
If you need to use the serial RS485 port on the TP1500 for the 314C-2DP, then it cannot simultanously be used for DF1 to the 1769-L31.
In that case you may have to use a gateway somewhere in the system.
Or add an ethernet CP343-1 LEAN to the 314C-2DP rack.
Or, change something more drastically...