Time change of 800xA and what is effect on PID Controller running plant ?
800xA 5.0 SP2 running with AC800M Controller
We need to change the 800xA system time by 1 hour what will happen to system.
1) What will happend to PID Controller (Runnig plant - Default PID lib is used no customization) ?
Any other issue ?
Aware of issues:
Even/alarm list will be effected by time
Trend will be effected ( Any issue with IMS server)
Exactly one hour?
If you adjust the time zone, system time is left unchanged.
Same applies to trends and alarm/event as they are internally stored with UTC time.
But if you keep the time zone and change the system time, every place where time is used will be affected. Probably not a big problem though.
I can't tell how a PID loop in an AC 800M will be affected - if it run based on timers (not actual clock time) I suppose nothing will happen.
Basic History will record double values if system time is backed.
IM History will stop recording one hour unless purge of future time is made (see manual) after backing the time by one hour. A forward time set will create a "hole" in most trend servers.
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