Trends limit increase upto 1 Year
I have a system of 800xA with Bailey Infi90 PLC. I want to extend trends record limit to 1 year. How i changed the settings? Currently we have 6 PLCs and all PLCs trends limit is different this problem i can't understand.
Answers
Use Hierarchical logs
In System 800xA, the length of a trend log is defined on the Log Template. The Log Configuration aspect has a link to the template.
For Basic History, set the log period as you find appropriate. Each sample allocates roughly 24 bytes on disk. Can be edited at any time.
For IM History, the log period cannot be changed. Drop log, adjust old template or create a new, create new log.
For 800xA History, the log period is set in RTDB and may be automatically cut down, e.g. if disk space runs low.
If you add a hierarchical log, remember to use Timeaverage treatement in your trends as the Momentary (legacy) and ExtMomentary treatments rejects calculated values. The two momentary treatments are only suitable for short trend scopes. For longer scopes (two digit hours) it is recommended to use TimeAverage.
Don't add hierarchical logs to counter a too short primary log.
For Basic History, set the log period as you find appropriate. Each sample allocates roughly 24 bytes on disk. Can be edited at any time.
For IM History, the log period cannot be changed. Drop log, adjust old template or create a new, create new log.
For 800xA History, the log period is set in RTDB and may be automatically cut down, e.g. if disk space runs low.
If you add a hierarchical log, remember to use Timeaverage treatement in your trends as the Momentary (legacy) and ExtMomentary treatments rejects calculated values. The two momentary treatments are only suitable for short trend scopes. For longer scopes (two digit hours) it is recommended to use TimeAverage.
Don't add hierarchical logs to counter a too short primary log.
Please take a screen capture of your Log Templates (be sure to include the Data Collection tab) and post as an answer to your own question.
Here an example of a three level hierarchy (first and second in Basic History and third in IM History). Notice that second and third level is calculating an average value based on a number if samples from the closest faster log.

If your logs uses different templates, log lengths may vary. If you want all logs to be the same, I suggest to use the one and same template.
Here an example of a three level hierarchy (first and second in Basic History and third in IM History). Notice that second and third level is calculating an average value based on a number if samples from the closest faster log.

If your logs uses different templates, log lengths may vary. If you want all logs to be the same, I suggest to use the one and same template.
The trend limit is not different depending to the controller, it is different on every tag.
We have set 2 weeks of basic history on all tags, but in reality all tags have longer times: something between 3 and 6 weeks.
Seems the set time is promised, but if the system is in good mood and there is some space left the data is hold longer.
I guess there is a relation between how often and how fast the measured values are changing, and the hold time.
We have set 2 weeks of basic history on all tags, but in reality all tags have longer times: something between 3 and 6 weeks.
Seems the set time is promised, but if the system is in good mood and there is some space left the data is hold longer.
I guess there is a relation between how often and how fast the measured values are changing, and the hold time.
I increased time from 4 weeks to 08 weeks and its update successfully but no trend on any tag... Is it take some time?
Add new comment