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Problems linking memory bits to inputs values

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I'm using a V120-22-UN2 PLC. I have some troubles using input switches values to set or reset memory bits.

Actually, I managed to control one memory bit on the first net I have created: a direct contact using the value of my first input ( I0 ) is linked to a direct coil assigned

to the first memory bit. I even used the inverted value of the memory bit to contorl another one and I had no trouble.

But, when I try to assign a new memory bit to another input value using the same configuration, there's no change in the memory bit value. Actually if I use the online mode, I can notice that everything is goin well for the contact (the wire gets red when I pressed meaning the current flow is allowed to pass the contact) but then the memory bit's coil stays inactive.

I have joined a screen print of both switches.

Any help on this matter will be the welcome

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  • MVP 2022

Just a few suggestions:

1) Make sure the coil is not duplicated elsewhere in your project.

2) Make sure the subroutine the coil is in is being called by the Main routine.

3) Make sure the ladder rung is not disabled.

4) You can't make online edits, be sure to re-download the project to the PLC after your change.

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