The panels I am considering this filter for are sub-fed from a PDU. Harmonic content is about 80% current THD, Voltage THD at 1.5%. Amps are 7.5A / phase, 13A on the neutral (this is on the feeders). These are a pair of feed-thru 100A 42 space panel boards. At the rate PC's are added to these panels, I'm concerned about cooking the neutral and ground.
I have found an RMS value in excess of 35 amps flowing on the ground back to the UPS, on a #4 AWG. There are many frequencies riding on this wire. (up to 10kHz).
I believe I have two issues here; fundemental voltage distortion will increase above 3% soon from additional PC's. And 2nd, stray oscillary transients run along the grounds. If left unchecked, something is going to fail.
