Integral X (t) vi

[Peejay]

Hi,  I am using Labview 8.2 and I am trying to integrate a

60 Hz sine wave coming from a AC power source ( via DAQ).

My question is how do you set the value of dt within the integral x(t) vi?

Whenever I set this value (lets say 0.016) and run the vi

continously it automatically sets back to zero.

Thanks,

PJ

PJ

[Dennis_Knutson]

I don't understand what you are doing. There is nothing that should be run continuously and you simply pass the value of dt to the integral function.

[smercurio_fc]

It also makes no sense to use 0.016 as dt. dt is the sampling interval, not the period of the waveform. I suppose one should ask: do you know what an integration of a waveform is? It's basically the area under a curve. There are various numerical methods to implement this on a computer, with the trapezoidal rule being one of the simplest.

Also, integrating a sine wave just gives you a cosine wave - i.e. a phase shift. More specifically, it's -cos(x) + C, where C is some constant. That's just simple mathematics.