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Logging of boolean shared variable data using DSC module

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I am working on a project that involves a decent number of double and boolean shared variables. The alarms and data need to be logged. By setting the resolution of double SVs, I have manged to control the amount of data logged. However, I am not yet able to handle the issue of boolean data types. (These indicate ON/OFF state of various components). I just want to log data points on value change. As I am new to DSC 2017 any suggestion would be helpful 


Another small question the scf file format used in earlier DSC versions. Is it also available with DSC 2017?



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Message 1 of 6

Any suggestion??

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Message 2 of 6

Scf files are not supported any more but there is a migration tool (under Tools->DSC), although I never used it.

The documentation I read says nothing about how logging is optimized (if ever) for a boolean value.

My guess is that logging occurs only when values change. A small test project may give you an answer quickly.

If there is no optimization, you may consider using numeric variables instead of booleans.

LV 7.1, 2011, 2017, 2019
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Message 3 of 6

Thanks for the reply


I converted boolean SVs to Integer but no improvement. The library has 2600 SVs, I even disabled logging of Alarms but still the problem persists. As the application runs for an hour then database size is around 1.5GB..really stuck at the moment 🤔

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By disabling the generate event on value change property on the ALARMING page I have managed to address the database size problem, the alarms are logged and retrieved fairly efficiently; so a big step forward. However, despite logging being enabled I am unable to see any data in Citadel.

Are there any special setting for logging data for boolean shared variables.   

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Message 5 of 6
Accepted by topic author Nustian

SOLVED: the logging option was unchecked for most SVs. 

By disabling the generate event on value change property on the ALARMING page  the database size remains manageable.  

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