Dear Forum Members,
the picture below shows a temperature trend.
From this trend, I need to create the following Event Frames hierarchy:
Profile (Parent EF)
|_ Step 1 - CH1 (Child EF)
|_ Step 2 -PI (Child EF)
|_ Step 3 -CH2 (Child EF)
|_ Step 4 -MHT (Child EF)
|_ Step 5 -Ref (Child EF)
The Step 1 increases until 150°C.
During the Step 2, the temperature is around 150°C.
The Step 3 increases until 385°C.
During the Step 4, the temperature is around 385°C.
During the Step 5, the temperature decreases until 87°C.
With a PI Analysis, I am able to determine when the step 1 starts and finishes, when the steps 2 and 4 starts, when the steps 3 and 5 finishes.
If I determine when the steps 2 and 4 finishes, I will be able to find when the steps 3 and 5 starts and vice versa.
My difficulties is to determine when the steps 2 and 4 finishes or when the steps 3 and 5 starts.
So how can I finishes and starts a PI Event Frame at the moment where the temperature increases (step 2 to step 3) and decreases (step 4 to step 5)?
For the start of Step 5, would something like the DeltaValue method be of any use for you?
It is a method that returns the difference between an attribute's value and it's previous value. So, if DeltaValue becomes negative, then it should mark the start of Step 5.
One potential issue is that this starts the event frame "one value too late".