AC conduct time measurement by DAQ

[yangyang-rexxar]

Hello everyone,

I have a question on how to calculate a time period of an controlled AC waveform. You can see in attached files there are 2 types of waveforms, in both of them, I need to measure the time from angle 1 to angle 2. In past few months we used VI "Transition Measurement" to measure a 5%-95% transition time, but the result value is smaller(7.2ms) than what I get by a scope(7.4ms). Is there any other arithmetic to do such a calculation precisely include 100% field included?

Please advise. Thank you.

Image 1

Image 2

Message Edited by paulbin on 02-23-2009 03:49 AM

Message Edited by paulbin on 02-23-2009 03:50 AM

Message Edited by paulbin on 02-23-2009 03:51 AM

[yangyang-rexxar]

I do use a current transformer to convert AC waveforms to a low voltage signal to measure it by DAQ card, but the pictures I showed above are captured by scope:)