Hi,
Here's what you need for your application:
1. According to the magnitude range of your voltage and current signals, choose suitable DAQ devices for signal acquisition. Notice that the DAQ devices must have simultaneous ADC. C module 9227 and 9225 are recomended.
2. Use the example 'Basic Power Measurement.vi' that provided by our EPS toolkit to measure the value of the input voltage and current and also their phase difference.
Notice that the measured value 'power factor' by this example is related to the phase difference between the input voltage and current.
You can find further information here.
Thanks,
Yifan