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Posted: 2023-01-31 02:52 AM
I would like to know how to disable data backup (memory persistence) on a warm start on a M221 PLC using Machine Expert Basic as programming software. In other PLCs like Allen Bradley/Rockwell or Siemens you have the option to select which symbols/memory area you want to persist.
What is currently happening:
Both %M and %MW registers are being saved, so when PLC loses power and gets power back, it restores the values.
What is my expectation:
Be able to control which symbols/memory area is going to be persisted or not.
Current workaround:
On the ladder in case I detect on the first scan a Warm start I trigger (force) a Cold start (%S0 to 1)
Is this possible on this PLC/Software?
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Posted: 2023-01-31 12:38 PM
Hello,
Yes you could reinitial the values with %S0. If you did not want to have these values persistent use an other memory space. the first 50 words are peristent per default. If you use word in a higher memory range these words are not longer persistent.
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Posted: 2023-01-31 12:38 PM
Hello,
Yes you could reinitial the values with %S0. If you did not want to have these values persistent use an other memory space. the first 50 words are peristent per default. If you use word in a higher memory range these words are not longer persistent.
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