CIP Data Table Read CompactLogix and ControlLogix

I'm having trouble reading data from a ControlLogix PLC to a CompactLogix PLC. (Adding the I/O and using produced/consumed tags is not an option).

My ControlLogix is a 1756-L61 w/ a ENBT/A in the first slot (next to processor). It's IP is 10.113.101.35. I'm trying to read a DINT Array of Length 17. (DINT10[17])

My CompactLogix is a 1769-L32E w/ a front face Enet port. IP is 10.113.101.35. I'm trying to put it into a DINT array of length 17.

The path, I think, is what is tripping me up.

I've got 1,1,2,10.113.110.35 and when I go back to it, it changes to LocalENB,2,10.113.110.35. It still gives me an error code of 16#0004 and the Extended Error Code is Blank.

I need to read the data from the Control Logix ... what's the problem?

Thanks,
Jason

place a 1,0 at the end of that communication string.That would extend the message to the backplane then to the card in slot 0 (which in this case is the processor)

Oakley said:

place a 1,0 at the end of that communication string.That would extend the message to the backplane then to the card in slot 0 (which in this case is the processor)

Click to expand...

Ah, ok. Thanks That worked. How would this string change if it were CompactLogix to CompactLogix?

Thanks,
Jason

Lakee911

I'm sure it must be a typo - but you said both ethernet ports had the IP address of 10.113.101.35

This might seem obvious, but they have to be different addresses

Still, the path specification is made much easier if you can "browse" to the target device using the button in your message configuration dialog. This assumes that you can put the remote ENBT module and ControlLogix controller in your Compactlogix I/O configuration. This can only be done Offline, so will need a download, therefore you may be stuck with specifying the path as you have already done. You say adding the I/O is not an option, presumably because the controller can't be stopped, but if you ever get a chance to, it is worth doing it for clarity and documentation.

That is a typo. The IPs are different.

Why is adding the I/O better or worse than MSGs?

Thx
Jason

Defining the path to the remote processor using the I/O config tree is better only from a documentation perspective. It makes no difference in the actual execution and you still have to use the MSG instruction. It just simplifies the path definition within the MSG instruction.
The biggest advantage with the I/O tree is that you can place a name to the remote processor. Once this is done, the path selection within the MSG instruction would simply show this processor name and nothing else. You don't have to worry about the LocalENB,2,10.113.110.35,1,0. You would just see "RecvPLC" or whatever you decide to name it. If I'm troubleshooting this MSG in the future, 10.113.110.35 requires me to dig deeper to find out what processor this is going to.
You've already seen how your 1,1 got replaced with LocalENB. This is because LocalENB is defined in your I/O tree and RSLogix shows it instead of 1,1 since it is easier to follow.

Oh ok, that does make a lot of sense to do it that way when possible. Cool. Thank you.

Lakee911 said:

Ah, ok. Thanks That worked. How would this string change if it were CompactLogix to CompactLogix?

Thanks,
Jason

Click to expand...

A co-op student in my department had to do a message from ComptactLogix to ControlLogix and the format was 2,192.168.1.1,1,8. i.e. exclude the rack and slot designation at the beginning. The leading #2 in my example indicates ethernet IP communication. I have to assume that CompactLogix to CompactLogix would be the same format.

Welcome to the Forum, Bgrant !

That thread was about seven years ago, and in the meanwhile there's been a new family of CompactLogix controllers developed called the '5370' series.

One of the changes to the 5370 series controllers (the L1, L2, and L3 families) is that the Ethernet module is both physically and logically integrated into the CPU.

So instead of treating the Ethernet module like it's in a "virtual backplane in Slot 1", you address it as though it's a port of the CPU.

An outgoing message from a 5370 series CompactLogix on Ethernet can start with "Port 2, IP Address".

And a message targeted to a 5370 series CompactLogix can stop at the target IP address (just like an SLC or PLC-5 or MicroLogix target).

The addition of the "1,0" port and slot will still work, but it's no longer necessary.