phase difference

[poo123]

I am trying to measure the phase difference between  two signals of a RLC series circuit with a shunt resistor. One of the signal is the output volatge and the other is the voltage across the shunt resistor. The difference in phase between the two should be less than 90 degrees but for some reason I am getting greater than that.  I am using extract single tone information Vi to measure the phase. I got the phase difference by changing the reference signal but still I get the difference way greater than 90.

[RavensFan]

You'll need to post your code and some screenshots of the waveform signals that you are getting for anybody to be able to help.

[poo123]

I have attached the screen shots for two different frequencies and the code .

For 30khz, phase difference=(200-(-184))=384

For 50 khz, phase difference=(191-(-241))=432 deg

[TLE]

These might help:

http://forums.ni.com/t5/LabVIEW/Help-with-phase-difference-of-sine-waves/m-p/1067383#M473245

http://forums.ni.com/t5/LabVIEW/Interchannel-delay-and-phase-measurement/m-p/1100081#M486409

http://forums.ni.com/t5/LabVIEW/how-to-plot-phase-difference/m-p/1125329#M496744

http://forums.ni.com/t5/LabVIEW/phase-difference-between-two-sine-waves/m-p/916012#M412357

[RavensFan]

It's not just greater than 90, it is greater than 360.

Try using quotient and remainder function and divide by 360.  You'll see the remainders are 24 and 72 degrees, respectively.