MOV Function

[lekuru]

Maybe someone can please shed some light into my situation. My initial value is set at 15000 (O:0.5), but when pulse equal 10 i want to subtract 1000 once from my initial value and the new value will be 14000 from their on untill we turn off the equipment. My problem is that even though it subtracted 1000 from the initial value it still put back into(O:0.5)instead of 14000 the new value, please help any hints or insight into this will be greatly appreciated.

 

[Skogsgurra]

Tis could be a case of a severe "sticky" 'o-zero-five' or the 'number won't go away' syndrome.

You find manifestations of this syndrome in the peculiariestest places. Can be in your collegues mail-box, in your PLC program or your girlfriends locker at the gym.

Before you have given us more information, I am afraid my guess is the best answer you will get. And, I must confess, that is not a very good answer.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[controlsdude]

My best guess would be the following:

Your intial value qualification is true all the time. Probably need to change this to a one scan condition when doing the intialization procedure.

Also when moving values into an output only do this once in the program, always use a buffered data location to perform any math or manipulation of values.

 

[PLCMentor]

Maybe you should post some of your code to show us what you are doing. Sounds like you are not really doing the subtract command or maybe you have some initialization logic that initilizes it back to 15000 and it is getting activated. some times you will have to add logic to your program to allow you to see what is happening.

Russell White, P.E.
Automation Technologies, Inc.

http://www.AutomationNC.com

Automation Help

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