09-05-2008 09:26 AM
09-05-2008 11:42 AM
09-05-2008 12:59 PM
We use expressions, with the qgood parameter added to the input (level). level*qgood(url of level)
Would bring value to 0 in signal is bad quality
We also have noticed that when using modbus, the trend will be "missing" the data if the site goes out, comm fail
Mike
09-05-2008 01:28 PM
Mike
Thanks. How does qgood know that data is not good? Is it based on data that stays the same exact value over a certain period?
09-05-2008 04:52 PM
QGood() and QBad() uses the lookout quality features for object properties/data members. An example is the Red X that goes across objects that on no connected. Some drivers do not have quality features (we have a custom driver that doesn't use quality features). Modbus uses the quality features.
Good luck
Mike
09-08-2008 02:50 AM
I cannot use value of zero as indication of bad quality, because this value can be real value of measurements. The best way is to stop logging to Citadel if comm failure occurs (mark trend line with different color would be great options too).
09-08-2008 09:01 PM
Maybe this is a workaround for you.
You can create an expression not(qgood(level)), and log this exp. The hypertrend has a datamember hideIfOff. For example, the exp is in group1, trace2, turn on hideIfOff1.2, then there will be a line when the quality is bad, and no line when quality is good.
This line can be a reference for you that indicates when the quality is bad.