Micrologix Error Codes

I have a micrologix 1000 controller that occasionally faults out.

I get a Fatal Internal Hardware Error occured S:1/13 also S:5/8

When I clear the Major error it puts a 0 into S:1/13, but if I try and go back into run mode, it Faults immediately.
If I clear both S:1/13 and S:5/8 to 0 it Runs fine, but after a day, or an hour, or 15 minutes??? it faults out again.
I'll probably just change out the controller, but I was wondering if anybody has seen this error before.



Thanks
George Bradley

I saw a similar series of errors happen at a client site and eventually the PLC had to be replaced... I dont know if the problem was exactly the same but from what the client desribed it is pretty similar. 2+ months since replacements and havent seen a problem.

One way around it is setting a bit to clear any errors at powerup. I think its is S:1/8.. Something on the lines of Fault Override on Powerup. You can set that to '1' and that will clear any faults on powerup though it still will not resolve whatever is causing the PLC Shutdown after 'X' hours.
Good Luck!

Almost always, error code 0x08 and 0x09 are caused by either by incoming power line noise, or unsuppressed inductive outputs that are feeding back voltage spikes into the controller.

Usually these result in a corruption of RAM memory, which in turn fails the next scan's checksum check and stops the controller, which then reloads the program from NVRAM. That's why the "retentive data lost" bit comes on.

A fat green ground wire is my favorite fix for noise problems, but you should check any inductive outputs to see if they've changed (like a motor starter being replaced, but the snubber not being replaced).

It's possible for this to really be a gradually failing RAM or other processor component, so you may need to replace the processor anyhow.

Ken Roach said:

A fat green ground wire is my favorite fix...

Click to expand...

I like that.

Well this unit is one of about 12 that are faithfully chugging along side by side without any problems.
I already replaced it with a new ML1000, but if the replacement somehow goes south I know what to look for.
Thanks

Ken Roach said:

A fat green ground wire is my favorite fix for noise problems, but you should check any inductive outputs to see if they've changed (like a motor starter being replaced, but the snubber not being replaced).

Click to expand...

Hi Ken Roach, I have the same trouble. Can you explain me more about your "fat green ground wire" method?
I am tend to write some more code to clear these error bits at powerup, but I am afraid that I will cause fatal error and may affect the PLC seriously if there is actually a error or electrical overload. So is it not a wise way?

thank for any helps

leoxdragon said:

Hi Ken Roach, I have the same trouble. Can you explain me more about your "fat green ground wire" method?
I am tend to write some more code to clear these error bits at powerup, but I am afraid that I will cause fatal error and may affect the PLC seriously if there is actually a error or electrical overload. So is it not a wise way?

thank for any helps

Click to expand...

See PDF below. In the US the ground wire is "Green"