9030 Battery

I am having a hard time with the BATT LED on the 9030. I have replaced the battery a couple times with 2 known good batteries, cleared the PLC fault table, but it still thinks the Batt is no good;("Failed Battery Signal") red LED remains ON, any idears?

Sounds like a hardware problem. Swap the power supply with one from an expansion rack. If the problem persists, it's probably in the backplane.

The tried and true method of covering the LED with a piece of black electrical tape might also work.

I like the tried and true method the best, however; if the CPU thinks the batt is dead (which it does due to the constant log in the fault table)will this PLC suffer the same symptoms as a unit without a batt at all. I think that means loss of any memory after certain period without power? This will not work for me as the customer will have this unit down for several hours/days at at time.

There is a diode between the battery and the backplane to prevent the battery from supplying power when external power is applied. Somebody probably let the smoke out out of it, so the battery is isolated from the CPU. If battery power can't get to the CPU's RAM, then you'll lose your data when the primary power goes off.

If you put the power supply that generates the 'low battery' fault in an expansion rack, you get to keep the power supply. The battery in a power supply in an expansion rack is as useful as a gelding on a stud farm.

Thanks for the info Steve, never seen a gelding on a stud farm before but you are correct, swap PS and she's OK.

What is a gelding anyway?

A gelding is a horse that used to be a stallion.

that must hurt