Trend one scan pulse in Rslogix5000 V19

[hani2018]

Try to trend one scan signal in Rslogix5000 V19, but find sometime the pulse is missing in the trend. I use 1 ms sample period, the PLC scan time is about 20 to 30ms, why one scan pulse still can't be captured by trend?

 

[widelto]

My guess is that one scan signal will never be visible on a trend, but instead you can latch another tag and see when the original signal ocurred.