Allen Bradley 1747-ASB

Hello Everyone,

Im struggling with a plc that we got here in the company where I work at. We use this plc for precooler temperature monitoring only. The plc is mounted on a panel with one main expansion board 10-slot with the AB SLC-500, one output card(dry relay), and six rtd input cards, and a scanner. A secondary, remote 7-slot, expansion board is installed with an AB 1747-ASB remote adapter installed. Lately i got a fault code "8". Going back to the troubleshooting manual, it says that the adapter is still on the Power Up Self Test in Progress, and it recommends to replace the card. I ordered a new card, and as soon as I installed it with the same dip switches settings, the new card went straight to a fault code of "8".

What am I missing?

Thanks in advanced.
Omar Gomez

Not sure what to say as i have never had an 8 error code

8 is a power up self test at start up and only for a few seconds normally
Also an 8 or 333 is a watchdog error

Some thoughts

1. What series was the old ASB - What series did you replace it with
2. Can you swop out the SLC rack - Backplane
3. Has anything changed since you started getting the intermittant fault
4. Earthing on the rack all good
5. Have you checked the logix asb config to make sure its correct (and dip switches)
6. What do the LEDs on the ASB do
7. What module is the other end and what (if anything) does this show when under the 8 fault
8. Does the SLC record any faults

Quite likely a bad power supply in the remote chassis.

Hi

I would also start with the power supply on the remote rack as over the years I have replace a few of them

Donnchadh