prog. gets deleted on L32E after power fail

[ssp657312]

I have two different machines that have failed They are Compact Logix based, 1769-L32E CPU. The manual specifically says if the battery is OK and able to retain the program that the BATT LED on the face will be off. Every time we have checked on the PLC the BATT LED is off. If you unplug the battery or it is more than 95% depleted the LED will be red. I have unplugged the battery before and have verified that part to be true. However a few times a year a safety conditon will trip the whole electrical panel, turning off the PLC power. It SEEMS like with a fresh battery it is able to power back up but as the year progresses, if we are pushing a year or so, the next time we loose power we loose the program. We will find the panel powers back up in the RUN mode and all of the HMI displays are showing ???? (as in communicating but address not found) because when I get the laptop out I find there is no program in memory.

 

[deemon113]

I have had this problem myself, and the way I rectified it was by putting the PLC on a UPS or surge protector.

I hope that can be of some help to you.

 

[Mark Buskell]

I have this problem as well on 2 L32's. This happened during a power interruption. We added a compact flash card to them and set them to auto recover on corrupt memory.