MVP 2021 Flex727 Posted May 4, 2022 MVP 2021 Report Share Posted May 4, 2022 Anyone have a bullet-proof solution to activating a positive transition contact exactly once per week (using VisiLogic)? This needs to be able to deal with undetermined power-off situations. Every solution I come up with has a flaw that can occur if the machine is powered off multiple times during the week or is only powered on the last day of the week. This solution fails if the PLC is powered on at any point during the week after midnight on Sunday. Adding an inverted contact of SB 2 allows the logic to work if the PLC is powered on at any time on Sunday, but will fail if the PLC is power cycled during the day on Sunday and will still fail if the PLC remains off on Sunday. Changing the comparison to >= will cause the logic to fail if the PLC remains powered on continuously. Every solution that is more complicated still requires the PLC to know that a new week has begun (set & reset bits, etc). Anyone have an answer? Quote Link to comment Share on other sites More sharing options...
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