Trending stop at some period (Data is missing)
Two question about Trending,
First, we found that sometimes Trending (using Trend acquisition function block) didn’t acquire data at some period (screenshoot attached). I am sure there was no activity (ie. configuration) that may interrupt trending, and there was also data change between that period
Second, sometimes Trending doesn’t start automatically after I do “whole station” load to a Operator station. I see ACT status on one of trending data acquired in DigiBrowse, but the End date isn’t current date.
1) We use Freelance 2013 SP1 RU1 with AC900F redundant controller. There are 4 Operator stations connected to the controller.
2) Please find attached screenshoot regarding our Trend (TRN) configuration
3) All Trend acquisition function block was made inside one FBD program. Do we need to separate the FBD program, or even separate into one TASK with certain configuration?
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let’s check basic things first,
Timesynch is enabled on all node and on controller time is set, means set system time performed ? If so the controller res.datetime system variable time and all digivis time(at right hand side corner down) should be equal. Also in controller webserver controller clock time should be in synch.
not an answer but analysis to your question,
Q1 : From attached image seems entry 38432 to 38442 values are updating/acquired at every 5 sec. But then there is gap of 4 hours(that's strange) and then again values are updating/acquired at every 5 sec. But the values in 3rd, 4th & 6th column have drastic change after gap !
Can you check system and process alarm @ DT#2016-09-06-10:55:51.100, also @ DT#2016-09-06-14:53:36.100 time ? in message list what's going on at this time ?
Q2 : Trend line start appearing automatically once Freelance operation is in running status and timesynch is proper,
As such there is no option or button on trend display to start trend manually, or it cannot be configurable. then how you start trend when it doesn't start automatically ? What time and date it shows on trend display after "whole station" download to a Operator station ? why you are checking in DigiBrowse ? it should first appears in trend display....
Few more questions, on tab "area option" is tehre any time gaps set ? or it's default setting ?
Regarding question ,for information 3) No it's fine in one fbd under one task, But how many trend aquisition function blocks you have ? what is task cycle time? and and type ? load optimal or equidistant ?