Total Harmonic Distortion

I have a customer that is going to use a SNAP-AIPM-3 for a 3-phase motor. In addition to voltage, current, true power & apparent power they want Total Harmonic Distortion. I am wondering if this could be calculated in PAC Control? Any thoughts? The formulas I saw online for Voltage and Current THD calcs look straightforward, except I am not sure where the nth harmonic values would come from. Thoughts appreciated. I know there are power quality analyzers out there that do this, but wondering if it can be done with a PAC.