Reading data from a CompactLogix to a MicroLogix 1400

[Welshy]

Hi everyone,

Brief overview of the issue:

I have a CompactLogix (pt No:1769-L36ERM) that is connected to a MicroLogix 1400 (Pt no: 1766-L32BXB) via Ethernet. Data needs to be passed to the MicroLogix from the CompactLogix to then be sent onwards via a RS232 connection. Due to company standards I'm required to put the messaging instructions in the MicroLogix, so the Micrologix will read the data from the CompactLogix. Unfortunately I have none of the kit with me for testing.

The issue is I'm unsure how to configure the message instruction in the Micrologix (RS500) to correctly read the data from the CompactLogix and I don't have any test kit available to play with to see it working.

Currently I've set up the following:

In the CompactLogix (RS Studio 5000):
All data is placed in an array (array tag is N10[0])
Map PLC/SLC Message - set to map file number 10 to Name N10


in the Micrologix:
Msg instruction created
Set up the Msg instruction as follows:
channel: 1 [integral]
Communication command: CIP generic
Data Table: N10:0
Size:12

Then what i'm less sure about is the target device data i need to input, The Service (Generic Get Attribute?), Class, Instance, Attribute. I can't find any examples of this online.

So if anyone has any good tutorials on how to do this that would be great or could run through it for me I'd be super grateful. Please let me know if you need any more information.

 

[Saffa]

You want to use a SLC Read message type in the Micrologix MSG block, not a CIP Generic. Once you select that you'll be able to type in N10:0 as the data table address, and how many words to read.

Rest should be easy from there.

 

[Welshy]

Thanks for the response, the only Read Comms commands available to me in the msg block are 500CPU Read,485CIF Read, PLC5 Read, and CIP General. I'm assuming the SLC read would be the 500CPU Read?

 

[Nova5]

500 CPU is a SLC 500 series, so yes thats what you need.

 

[Saffa]

Thanks for the response, the only Read Comms commands available to me in the msg block are 500CPU Read,485CIF Read, PLC5 Read, and CIP General. I'm assuming the SLC read would be the 500CPU Read?

Yup that's right, sorry I couldn't remember the exact wording and the work laptop was packed away already!

Your compactlogix is essentially emulating a "Logix 500 style" data file, for lack of a more elegant description. So the Read in the Micrologix needs to match that.

 

[Welshy]

Brilliant thank you all for your help

 

[jimbom]

I have done this on my bench. You must add the micrologix 1400 in the compactlogix ethernet tree. Then it is just a matter of data allocation.

 

[Firejo]

In order to do messaging from the MicroLogix 1400 (or 1100 and SLC5/05) you not only need to select SLC type Read in the message instruction but you have to go into the CompactLogix and create a "PLC 5/SLC" Map. From the top of RSLogix/Studio 5000, select "Logic" and then "Map PLC/SLC Message". Under "File Number" enter the file number you're going to use in the MicroLogix (for example, if you are going to us N10:0, in the File Number enter "10"). Then in the "Name" field, select the tag in the CompactLogix you will be reading from (you will need to create the tags in the CompactLogix you are going to use first). The other thing you will need to do is use the "Multihop" in the message instruction. Off the top of my head I don't remember the path that needs to be used so I'll let someone else chime in on that.

 

[Saffa]

In order to do messaging from the MicroLogix 1400 (or 1100 and SLC5/05) you not only need to select SLC type Read in the message instruction but you have to go into the CompactLogix and create a "PLC 5/SLC" Map. From the top of RSLogix/Studio 5000, select "Logic" and then "Map PLC/SLC Message". Under "File Number" enter the file number you're going to use in the MicroLogix (for example, if you are going to us N10:0, in the File Number enter "10"). Then in the "Name" field, select the tag in the CompactLogix you will be reading from (you will need to create the tags in the CompactLogix you are going to use first). The other thing you will need to do is use the "Multihop" in the message instruction. Off the top of my head I don't remember the path that needs to be used so I'll let someone else chime in on that.

The OP had figured out the mapping in the Compactlogix already, but your description is great for anyone else needing to find this (its not that obvious where it is if you've never done it before).

I'm pretty sure in the Micrologix "Multihop" field, all you have is the IP address if both devices are on the same network and there's no routing through a backplane required. I've never had to do anything other than that so no idea how that works either!

 

[Firejo]

It's been a very long time since I've done this but I do have some recollection of having to define a path even with the CompactLogix always being at slot 0. Not saying that's the way it is, just a faint recollection.