Thanks for the reply. Here is what's going on to date. Grounds have been tested back to and including the ECG. All grounds were at 0.02 ohms or less. THD prior to filtering the input was 1.26%, 1.69 and 1.86 on 1,2, and 3 respectivley with the highest mag being 7.07 V. Drive outputs were a mess as expected. If you are interested in the testing report I can try to post a link. 6 AWG welder's cable was used to ground motor casings to the conduit (IMC) and from the drives to the conduit, and filters to the cases. Each was tested open on one end to act as a drain and connected at both ends for shield as recomended by two different E.E.'s. One drive has both an output and input filter installed(Transcoil V1K21A00 and KRF32ATB respectivley) There has been no improvement with these filters. We have moved the meter within the Tower yard to locations approx. 15 to 20 feet from the original location, run it on clean UPS power by extension cord and on line voltage from a panel served by a separate transformer and have run the meter without it's ground....briefly. We are now considering a completely different meter and a huge upgrade in filter. I'm trying to get authorization for additional testing. I'm thinking spectrum analyzer. I hate the fact that they are trying to fix this by throwing parts at it without knowing what they're aiming for.
