Communication Failure

I am currently trying to write ladder logic to monitor communications through ENBT modules in ControlLogix (L55) racks. Am I correct in my assumption that I can use the GSV instruction with the MODULE object and the Entry Status attribute to monitor these communications? There is an extensive example in the ControlLogix system user manual pg(6-8) but I think that this technique is for I/O modules only.

Is this approach the right way to implement this communication monitoring, or am I "barking up the wrong tree" so to speak.

Any literature or technotes that you could let me know about or any advice on how to tackle this issue would be greatly appreciated

Evidently if entry status is any other value than 4 the connection is not functioning properly. A screen shot. Thank you for your help

I forgot to mention that the program is RS Logix 5000. This seems like a fairly common feature that one would use for local indication of a commumication fault (a pilot light on the electrical enclosure).
I ask your opinion of my approach because I have not had to implement code to perform this function in the past and I find the GSV instruction and using the system objects somewhat confusing.
Please provide your opinion. Thank you all

Boy, I sure hope you all don't think that I am one of those
"gimme-gimme guys".

See Rockwell Technote 24162

The provided links and GSV techniques are the common and accepted methods for monitoring I/O connections in Logix controllers.

I use a simpler method when using distributed I/O that has a "Rack" object, like 1756, 1734 (POINT) and 1794 (FLEX).

Each Rack Optimized connection includes a "Slot Status" tag like this (FLEX example):

IOConnection:I.SlotStatusBits 2#0000_0000_0000_0000_0000_0000_0000_0000

Only the lower 8 bits are significant for Module status on FLEX, but when the I/O connection to the whole FLEX adapter is lost, all the bits go to 1.

The POINT adapter has two DINT tags, and 1756 has one DINT tag.

Thank you for the replies, my main concern was that this approach was only for IO modules and not for monitoring communication modules such as 1756-CNB and or 1756-ENBT. I appreciate the help.

Not sure if you can use something like this, but I have a ControlLogix L62 talking to remote point i/o modules. I am using a GSV with these parameters:

Class Name: Module
Attribute Name: Led Status
Destination: Connections (defined as INT)

The GSV returns the following:
1 = All Loss
2 = Some Loss
3 = All Healthy

Mark, I did read the manual on how to monitor the LED STATUS with a GSV instruction. At first I thought that might be the approach that I needed, but as I pondered it further I began to doubt that was the best way. It is entirely possible that I am over complicating the thing, but I will keep that (simpler) method in mind. Thanks!

If the ENBT is your primary communications port, how will you know if it fails?

Your control strategy should have monitoring - for example a heartbeat monitor.