Hmi not controling plc

[crankshaft 0]

Hi all I have CQM1H and a NS8 on a very simple line i have switch 1 turns on output 1 this works but i need to disable this from the hmi so i added a NC switch after switch 1 and while monitoring the ladder pressing the switch on the PT opens the line but does not turn off the coil. there is no other control for this coil I know this must be simple but so i'm I

[lostcontrol 23]

Are you absolutely sure? Can you post the CQM1H file? Is the NS8 object (21.06) momentary or maintained? (it should not make a difference however)

[Mark- 17]

Hello, Per your statement that the coil is not used in any other place in the program and I assume there is not any other place in the program that is writing to that memory with for example a block move or a file copy, the only way I can think that ladder is not executing is the examine off contact is in the program that is monitored but the program was not download to the PLC. The program that is executing is not the program being monitored. Good luck, Mark http://www.peakhmi.com/

[Jay Anthony 118]

Mark: Your conclusion is correct.

[crankshaft 0]

That's it. I had to download it again (maybe)and turned off the power and it works. thanks for the help