SLC500 Fault Troubleshooting

[JamesSmits]

I have an SLC500 with what appears to be a chassis configuration fault (S:6 is showing 0056). Chassis is configured as follows:
Slot 0: 5/02 CPU
Slot 1: Analog Input
Slot 2: Digital Input
Slot 3: Digital Output

Is there a way to check to see if the modules are detected by the CPU? This is an existing system that has been working for a few years, so I'm thinking I will find one of the modules no longer works properly.

Thanks.

 

[Aabeck]

If you can go online with RSL500 I would create a new project, then do a read of the IO through RSLinx. If a module isn't seen by the PLC it wouldn't show up correctly.

 

[JamesSmits]

Unfortunately I do not have RSL available at the moment since I'm in the field. I have access to a diagnostic panel that allows me to read and write registers. Is there a register that stores chassis configuration information?

 

[Aabeck]

I think that is deep in the internals of the processor, what you could get to in the S2 file would be the enable bits S:11/0 - S:11/15 that will turn off the control of the card, and checking of it.

If you turn off one bit at a time then try to run the program it might run without fault if the bad card is disabled.

But, if it's a rack problem it may effect all the cards.

 

[PLCnovice61]

So if you can see registered, doesn't that mean you can see the rack/slot in slc500?

 

[geniusintraining]

Just a shot in the dark but.... try removing the terminals to the I/O cards and see if it clears, this will tell you if its a short in the field and shorting out a card

Also the power supplies on the SLCs are the weak link so if you have one try changing it first

 

[parky]

Try powering down, remove & re-insert cards but I believe you have to rest the fault, it's worth a try