I don’t know what I did wrong, or what I don’t understand, but my tag historian is not logging any 0. The tag is the speed in FPM of a rollformer. Is it a normal behavior?
Tag Setup
Data in Sql DB
Here the history setup I have
Maybe I’m missing something but looks like you have it set up to do a minimum sample of 1 a second and the entries that your showing are about a second apart and it is showing variation in your data. Was it actually 0 at any of those points or is it just speeding up and slowing down but not sitting at 0?
Last value in database is 3 hours old
I’m assuming your actual tag value is 0 and your tag quality is good? I would expect it to log 0 if it went to 0 from the values you showed but I will admit in the past I have had the deadband affect values in ways I didn’t expect it to. I wouldn’t think that should be the case here though with as big of a jump as it would have to make to go from the last point down to 0.
Yes, tag quality is good, and equipment is done for today, so speed is 0. I will do some test with the deadband on Monday
Your max time between samples should be 1 second, not the min time.
A value of 0 with an old value of 0 will not trigger a deadband log event.
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Try changing your Deadband Style to Discrete. I typically have to do this with anything that goes from zero to non-zero like motor speed or pump flow rates. I only use Analog Deadband Style for things like temperature or tank level which are (hopefully) always non-zero.
Moving to discrete looks promising, but I’ll confirm Monday
Old value is over 100, not 0