1769-L32E Won't Recognize CompactBus Local

I've spent a couple of days in the field wrassling with a Compactlogix 1769-L32E rack.

Problem is neither RSWho or my RSLogix 5000 V16.03 software can see the local channels, Red 'X' in RSWho and yellow triangles in RSLogix 5000.

I have the project running in production on another similar rack with no problems, only difference is that the project that is running is flashed to 16.21 and the rack I'm trying to commission is flashed at 16.22.

I used the same program on the new rack that is in production, I changed the processor name and ethernet address in the new offline program, went online with a serial cable to change the ethernet address on the L32E.

I downloaded the revised program and everything looked good until I noticed the MS lights blinking on and off on my modules.

I've re-flashed the processor a couple of times.
One odd thing that I noticed that was the processor went to version 1.15 after one flash, but when it did, I was able to read ALL my local I/O in RSWho but no processor.

Appreciate any thoughts out there, hoping it's just the dumb stuff on my part.

-Dave M

Doulble and tripple check I/O configuration in project I/O tree matches actual real world configuration. e.g make sure where it says there is a 32 pt input card it really is a 32 pt and not a 16 pt.
Double and tripple check revision of I/O cards are the same as in project (major and minor revision number)
Make sure all I/O cards are installed corectly and lock latch is firmly engaged.
Check RPI in CompactBus Local connection tab is appropriate (should be 2.0 by default)
Check CompactBus Local module is not inhibited in CompactBus Local connection tab
Check all modules arent inhibited in each I/O cards connection tab

It sounds more than anything like a damaged Compact backplane connector or a missing 1769-ECR end-cap.

If it was just the RSLinx browse that omitted the [+] on the backplane, I'd say it was a missing EDS for the CompactLogix backplane object.

But since the controller itself says it cannot communicate with the Compact bus and the module blink their LEDs, I'm guessing an actual damaged hardware item.

Thanks Kiwi and Ken for the quick reply.

Hate being in the field when these things arise.

I'll triple check the slot config's vs the hardware tomorrow when I return to the site.

I also have a spare of all the hardware if needed.

Supposed to be on vacation next week to do some musky fishing back home so no pressure in getting this resolved so the equipment can start-up. hahaha

Thanks again

-Dave M

It was the dumb stuff

Hit the site this morning armed with a printout of the suggestions from kiwi and ken.

First thing I did was install a new 1769-L32E and fired up the rack..... same thing ... not recognizing local channels.
2nd thing I did was install a new AI module, it is the first module in the local rack.... same thing...not recognizing local channels. This took all of 5 minutes so it was worth a shot.

3rd thing I did was go through all the project configuration and matched up all of the items kiwi had suggested. Everything matched.

4th thing I did was go through ken's suggestions. BINGO!! No Right End Cap installed!... damn, I didn't do the harware install but should have found it earlier than this, I'm also new to Compactlogix hardware as well so really wasn't looking for one, only looked at the I/O modules.

Thanks a million kiwi and ken.
Embarrased to say I've been doing this kind of work since the early 1980's, mostly bigger PLC's without Endcaps

Hopefully I can help someone out in the future as I've been helped here.

Dave M

CompactLogix is its own animal. You have to learn all the secrets. The endcap has electrical components in it which terminates the bus. Without it, it doesn't work.

The same backplane and I/O structure is used in the Micrologix 1500, with the same type result if the endcap is missing.