Hi ,  
    I am a power systems engineer and I am new to Labview and Labview FPGA. The hardware that I am using is an sbrio 9642. I am using Labview 2013. The following is my application 
  
I have a three phase measurement of a substation. The three phase voltages are stepped down to +/- 2.7 v (270 volts actual). I am using the built in analog inputs to take these voltages. I have six inputs, two three phase voltages line to neutral. I want to measure the three phase frequency of these signals (Two frequency measurements in total). 
  
I want to use the built in three phase pll in the FPGA math and analysis palette. It is ideally built for such application. But, for some reason I am not able to get the right frequency (Which should be 60 HZ). 
  
I have also opened a discussion in the "Power electronics development community". I have all my files in this community. I recently found about "LAVA". So, I am posting this discussion again to get some help. I specifically want to use this method because in this way all the calculation will be done in the FPGA level and I can have the real time processor in the SBRIO for communication pruposes. 
  
For more information about this please check this link 
  
https://decibel.ni.com/content/message/63258#63258 
  
  
Frequency_calculation.zip