Allen Bradley to Schneider - CIP

[bjm79]

I am trying to talk between a Schneider Premium PLC and a Control logix processor. I have a TSXETC101 ethernet card in the premium PLC and a 1756-ENBT ethernet card in the control logix. I have managed to get the two connected (I can see the 1756-ENBT card from the premium plc) however, I'm not sure how to set up the messaging between the two. Does anyone have any tips?

 

[(8{)} ( .)]

To the best of my knowledge...

You'll need to have the CLX read/write to the Schneider PLC using generic messaging. The Schneider won't be able to read native CLX tags and I don't know of another way on ENetIP to get data out of the CLX.

There is the option of a using a TCP Client type command and format the string to match ENetIP commands (I just did this with CoDeSys so it works) but I don't know if the Schneider has this capability. If it does then you can read the tag data. It's not the easiest thing to do if you've never done this sort of thing so I'd go with the CLX being the master.

Another thing is to see how the Schneider is designated (ie. what Class of device that module is) and then set it up so that the CIP generic read/write from the CLX will "see" it (Class, attribute, instance).

I hope I didn't write something stupid

Good luck,

(8{)} .)
(Yosi)

 

[robertkjonesjr]

To expand on others comments, the options are:

1. CLX as Class1 scanner and the ETC module as Class1 adapter. This is implicit or IO communication using UDP (and usually multicast, but could be unicast). If the limits meet your requirements, this might be the best (easiest) option. The ETC supports three separate slave instance sets at around 500 bytes each (509 bytes T->O and 505 bytes O->T).

Since the CLX does not support Class1 slave adaptor functionality, it has to be CLX as scanner and ETC as adaptor.

2. Explicit messaging - use the CIP Modbus object and message from the CLX as client to the ETC device as server. In this way, you can read/write to any located variable (i.e. %MW1, etc) from the ETC.

3. Produce a tag on the CLX, and have the ETC consume it. If you add the eds file for the processor / Ethernet device in the ETC, you can actually enter in a produced tag name and read it using Class1 communications. However, this is limited as you can only consume data from the CLX so it is one-way communications.

4. Reverse engineer the native tag addressing protocol for CIP and use the SEND_REQUEST messaging block in the ETC to read a tag in the CLX device. As Yosi says, this is not for the faint of heart but it can work. RA has some guides that help on their website but you might need the ODVA specs, some reverse engineering from a known working driver on another product, and plenty of Wireshark to get it right.