lesmar96 Posted August 2, 2018 Report Share Posted August 2, 2018 Can any one tell me if the RTC on a Samba SM70-J-R20 updates automatically when daylight savings time rolls around? Quote Link to comment Share on other sites More sharing options...
MVP 2021 Flex727 Posted August 2, 2018 MVP 2021 Report Share Posted August 2, 2018 No it does not. Quote Link to comment Share on other sites More sharing options...
lesmar96 Posted August 2, 2018 Author Report Share Posted August 2, 2018 unitronics have any plcs that do? Quote Link to comment Share on other sites More sharing options...
MVP 2021 Joe Tauser Posted August 2, 2018 MVP 2021 Report Share Posted August 2, 2018 I made a daylight savings time subroutine in the long ago. Here's an export of it. The PLC has to have power applied when Daylight Savings Time kicks over. I always wanted to add sensing logic to see if it happened while it was off but never got around to it. If anybody wants to improve on this please share your work as I have. You can bring it into your project by right-clicking on "!Main Module" and selecting Import Subroutines. It uses MB 190 and MB 191. Then call it all the time from the Main Routine. Joe T. Daylight Savings Time.vlx Quote Link to comment Share on other sites More sharing options...
lesmar96 Posted August 3, 2018 Author Report Share Posted August 3, 2018 thanks a lot Joe Quote Link to comment Share on other sites More sharing options...
Bisku Posted August 5, 2018 Report Share Posted August 5, 2018 I use a subroutine that also works when PLC was powered down during Daylight saving time, allthough it is not perfect. When PLC was powered down during change of daylight saving time then the correction may be delayed up one week (but at least correction will be done at all). You will find the subroutine attached, but please keep in mind that I am living in Europe so different rules for start and end of daylight saving times may occur on your site, Feel free to adopt the data in line 1 and line 2 to your demands. DST.vlx Quote Link to comment Share on other sites More sharing options...
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