Trend Server & Archive Browser Freelance 2016
Hello
I have a question regarding the archiving of the trend's and the archive browser. I have in my project a Trend Server which is an Operation Station and an Engineering Station
The trends are about 630 signals divided into about 105 TR-DOS Trend Display that are in PANT (P_CD) and available in all operating stations.
1) He does the filing when he wants or that gives us the feeling. We are not clear when it generates another file. I give you some examples:
We thought that the files were created according to the time configured in the trend (Archive duration)
2) It seems that signal information is lost and does not even reach the dates that the file says.
In this case it is seen that the file T_75.001 the signals do not appear until 10-24-2019 and also that some signals are lost on the way.
We don't know exactly what is going on.
The questions in question are:
1) When do you archive the signals? and if something affects this (change of signals in the trend, change of time etc ...). When do you create the file?
2) We understood that the Archive Duration was the time that the archiving was going to take place. But it seems that it is not doing so.
We do not know if Freelance has any kind of limitation regarding the trend's.Would the solution be to export them?
Thanks. Regards
Asked 3 months ago
Answers
0
1) if you change something in the trend, the archive file will be zero'ed and the archived data is lost. This is one of the most annoying parts of the Freelance Trend system.
2) The archive files have a total limit of samples. If a signal changes fast, Freelance takes more samples to archive possible important events with higher resolution. This leads to less space for further samples.
So fidgety signals usually have a shorter time of available data than calm ones.
Edit: seems ABB have changed something in the Archive file behavior since we discarded Freelance Operations. So in 1) I may wrong.
2) The archive files have a total limit of samples. If a signal changes fast, Freelance takes more samples to archive possible important events with higher resolution. This leads to less space for further samples.
So fidgety signals usually have a shorter time of available data than calm ones.
Edit: seems ABB have changed something in the Archive file behavior since we discarded Freelance Operations. So in 1) I may wrong.
Answered 3 months ago
0
Hello Javier
The "normal" trend archives in Freelance are ring buffers, separate for every variable. A fixed number of cells is reserved for every variable, depending on configuration. On every scan (also depending on configuration) a value is saved into the next empty cell. If the last empty cell is full, the oldest full one will be overwritten.
This is complicated by the fact that only changed values are written into cells. If you have a trend configured for, say, 7 days, the saved history may be longer if the value changes only infrequently, e.g. a value changing only every 2 samples may go back 14 days.
(At least that's what I deduce based on my past Freelance experience.)
If you'd like consistently archived trends, one of the following is best in my experience:
Björn
The "normal" trend archives in Freelance are ring buffers, separate for every variable. A fixed number of cells is reserved for every variable, depending on configuration. On every scan (also depending on configuration) a value is saved into the next empty cell. If the last empty cell is full, the oldest full one will be overwritten.
This is complicated by the fact that only changed values are written into cells. If you have a trend configured for, say, 7 days, the saved history may be longer if the value changes only infrequently, e.g. a value changing only every 2 samples may go back 14 days.
(At least that's what I deduce based on my past Freelance experience.)
If you'd like consistently archived trends, one of the following is best in my experience:
- Use the trend archiving function (FTP server required, e.g. Filezilla)
- Use a third-party, OPC-based archival system
Björn
Answered 3 months ago
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