ControlLogix 5572 and MicroLogix 1100

So I have this new project of establishing comms between these 2 plcs. The ML110 is on a machine that tests parts at a specific temp based on part number, and this temp is currently entered manually. This machine has been located closer to the machine that makes the parts that get tested, and that machine has the CL5572 plc. So I boldly suggested that the CL5572 can send those temp settings (just a numerical value) to the ML1100 based on the parts that are currently running.


Knowing that it CAN be done versus me not knowing HOW to make that happen is my current situation.


So I presume that with the CL5572 I will somehow have to send data to the ML1100 via ethernet, but I am only guessing that it will somehow have to be thru the MSG instruction?!?!


Currently the manually entered temp settings are all be entered into an Integer data file (N7) on the ML1100. So the questions are: How do I configure the MSG instruction to send data to the ML1100 (step by step instructions will be greatly appreciated)? What do I need to configure on the ML1100 to receive the temp data into those Integer locations (N7)?


Additionally on the CL5572 there is a 1756-ENBT ethernet bridge, will this affect how the 2 plcs communicate? I'm hoping that I will be able to get this to work, as opposed to it being another case of open mouth insert foot!!! Thanks in advance!

Yes the MSG will work, you need to determine if your 1100 will send or will the CLX be sending, then make the instruction in that CPU to write to the other, the ENBT and 1100 need to be on the same network, see a few links below that should help

https://www.youtube.com/watch?v=vXjOpS8pbvg

http://literature.rockwellautomation.com/idc/groups/literature/documents/pm/1756-pm012_-en-p.pdf

In the CL5572 I would create an INT array first to hold the data you need to send across, eg. SentData[32] if you need to send 32 integers.

The MSG instruction in the CL5572 then needs to be set to a message type of 'SLC typed write', with the destination element set to N7:x, where x is the first register in the ML1100 where you want the data to land, and number of elements is how many integers you wish to send eg. 32. The source element is then SentData[0].
On the communications tab, you should be able to click the 'browse' button to 'build' a path to the ML1100 (first make sure your 1756-ENBT module is given a name in the project tree). Your path should look something like: ENBTModuleName, 2, IPAddressOfML, 1, 0.

No specific set up needs to be done in the ML1100 other than ensuring wherever you write to is not being written to elsewhere.

Agreed that the ControlLogix doing the write is the way I would do it.

Normally I would try to have the PLC using the setpoint read it instead, but the micrologix has one processor, and doing messages messes with the scan time quite a bit.

If you are also changing the setpoint manually (you don't have to), you can have the ControlLogix only write the setpoint after it has changed. Personally, I would read it back to verify that the change was made properly.

I would write to N11, and leave a few extra integers that are for future. Then in the Micrologix I would copy the correct N11 integer into the location that you use it now. But that's just my convention.

SLC typed write on the ControlLogix side, if I remember correctly.

thingstodo said:

Normally I would try to have the PLC using the setpoint read it instead,

Click to expand...

Agree, always try and 'read from' rather than 'write to' if possible, it makes it much easier to trace the source of a value in the future. Problem here is the ML has no facility to read from the CL, hence having to do it this way. You can 'map' the CL tagnames to be advertised as 'N' registers but I'm not sure this works with messaging anyway.

Wow, that was a lot easier than I was expecting. Using the CLX to write messages to the ML worked quite nicely, now I did this as a test at my desk but I did not have an enet bridge that is actually on the machine that I will be programming. From all suggestions here that should not be an issue. Thanks again for all the help!!!!