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2/12/2009 4:33 PM | |
Joined: 9/23/2005 Last visit: 9/17/2024 Posts: 4347 Rating: (1446) |
Hi, I suggest you change the direction of your program and base your time measurement in the internal runtime clock of the cpu. See FAQ http://support.automation.siemens.com/WW/view/en/26116927. see examples 5 and 6. so your program will be free of the worrys about SAMPLE_T, etc. |
Denilson Pegaia |
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2/13/2009 9:04 AM | |
Posts: 63 Rating: (19) |
SAMPLE_T is parameter for FB that is automatically updated during compilation of CFC charts and derives time between calls of FB. If you want to use it for time dependent actions you have to program yor timers manually for ex. OnDelay: IF Condition and ElapsedTime<PulseTime THEN ElapsedTime:= ElapsedTime + SAMPLE_T; ELSIF NOT Condition THEN ElapsedTime:= 0.0; END_IF; TimerOutput:= ElapsedTime >= PulseTime; Timer functions in SCL (S_ODT, S_PEXT, etc.) are in fact calls of standard timers, so they cannot utillize SAMPLE_T as a parameter. |
Last edited by: GrzegorzG at: 2/13/2009 9:06 AMLast edited by: GrzegorzG at: 2/13/2009 9:05 AM |
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