Hi Dojo,
we are using self-developed drivers / connectors for some elements which have only a limited and simple set of parameters. For some of these parameters we have trending activated in a trend template (real-time & average). But all we see is the real-time trend data, and no long term average data.
In the system settings we've set the TTL of the real-time trend data to 2 days (instead of default 1 day), and this has an effect on the trend graph as expected!
What may be the root cause for the missing average trend data? We've already checked the driver implementation and compared it to other drivers, also self-developed, where trending is working just fine.
Any ideas where to look at? Thank you very much! 🙂
Edit:
Meanwhile, we have discovered that the data type defined in the driver was the root cause for this issue. In the driver which was having trouble with trending this was set to "string" for numerical values we wished to trend - this was now set to "double" and trending looks good!
<Param id="34" trending="true">
<Name>Delay_1</Name>
<Description>Delay_1</Description>
<Type>read</Type>
<Information>
</Information>
<Interprete>
<RawType>numeric text</RawType>
<Type>double</Type> <- this is where the change was made
<LengthType>next param</LengthType>
</Interprete>
<Alarm>
<Monitored>true</Monitored>
</Alarm>
<Display>
<RTDisplay>true</RTDisplay>
<Positions>
<Position>
<Page>General</Page>
<Column>0</Column>
<Row>2</Row>
</Position>
</Positions>
<Units>ms</Units>
</Display>
<Measurement>
<Type>number</Type>
</Measurement>
</Param>
Great to hear you’ve found the root cause. Interprete type ‘String’ would indeed result in processing the value as a string, which makes it difficult to ‘average’. Thanks a lot for sharing the solution to this problem