rerice

Major Fault

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I recently had a processor have a major fault due to a power failure (which is another concern of mine) and when I went to go online with it alerted me that the program I am trying to load with is different than the program currently on the processor. Now I am the last person on this processor and have the most current file. I uploaded this program off the processor because now my curiosity is peaked and it is completely different than the one that was running on it before this major fault??? My question is can a processor have more than one program loaded on it (since I was under the assumption it can only have one) at once and if so how can I direct it to put the program I want it to load in after a fault. Or can I remove this other program all together. 

Next question is regarding this power failure fault... The processor is wired from a 24vdc panel and the panel is fed from a bank of batteries being charged from a La Marche battery charger constantly as long as there is line power. The battery bank gives enough time for the e-gen to start and give power back to the charger. With this set up the PLC never sees a power failure so how can the processor then fail? 

 

If anyone has had any experience with this I would love to here how you corrected it or if there is even a correction to be made. Thanks :)

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Which processor? Does it have a memory card in it? if so it can be set up to reload the program from the memory card and if the memory card hasn't been updated it'll load the "older" version of the program.

La Marche. Is it an old "UPS" or just a battery charger. The La Marche UPS wasn't the speediest at cutting over. If that's what it is I'm not surprised that it glitched

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You didn't say what processor it is. Some of them have an EEPROM or SD card and can be configured to load from flash in certain situations. When you make a change to the code, there's generally an additional step required to update the flash memory.

What model PLC do you have? Did you note the fault code before resetting it?

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Great minds and all that :)

 

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It's a micrologix or an SLC isn't it? 
Fault Code = 0002H  accompanied message:

"Unexpected hardware watchdog timeout or an ASIC reset occurred. Cannot go online or upload from default processor (no program). You must perform download."

This occurs from one of three conditions on AC powered units.

  1. AC power browns out slowly.
  2. AC power modulates below 50hz before failing
  3. The PLC is now a crippled self-bricking POS that can no longer hold a program past a power cycle.

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