PLC LOSS OF MEMORY

[Hellinas]

Hello,
Suddenly i found Allen Bradley plc without memory. Everything was red. The bat led was red and the led of o.k. too. The plc has UPS support and as i saw in the manual there is no reason to lose memory from a problem of the power supply. The operator told me that he found it in this condition and he didn't do anything. He told me that the p.c was on which means that we didn't have shutdown of the power. Has someone any idea about this?
Thank you in advance.

REMEMBER IT IS NOT GREECE IT IS HELLAS

 

[IRstuff]

There are too many possibilities to really say:
> someone cycled power and killed it somehow
> power spike or glitch clobbered the board or component(s)
> memory has actually gone bad
> process has actually gone bad
> entire board has actually gone bad

Assuming you've recycled power already and still found it failed, you need a new board, barring repair.

TTFN

FAQ731-376

 

[ScottyUK]

Replace the battery and reload the processor. See if it accepts the program. If not, bin it and start again.

Repairs are not usually economical on the SLC and ControlLogix CPUs; repairs to the older PLC-2 and PLC-5 are often both economically justified and practicable.


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If we learn from our mistakes I'm getting a great education!

 

[HEC]

What PLC, I have had similar problem with Allen Bradely PLC5/40, it would loose its memory once per month. When I consulted AB about the problem there was no problem. Until one day a firmware upgrade turned up in the post with a note to upgrade this and our loss of memory problem went away! I do not recall the firmware version numbers, the PLC was installed circa 1997.

Mark Hutton