Gfi

[dewexler]

I have a tool with 3 GFI, Main 200A and an 80A followed by a noise filter, cable, and another 80A GFI. The 3rd GFI is fine, no trips. The 2nd GFI, 80A has intermittantly triped several times, even with tool idle. The 3 GFI's are supplied with 120vac for operation. If the 3rd GFI never trips, then we are assuming the noise filter is causing the 2nd GFI to trip. Can you give us some help of what we are looking at, and is our noise filter the most likely culprit?
Dave

 

[tom baker]

Whats the trip level of the GFIs? can you swap them to see if the problem stays or follows?

 

[LarryFine]

Dave, it is likely that the line-to-GEC and/or neutral-to-GEC components are resulting in a line-to-neutral current differential, or imbalance.

The best test is temporary elimination of the filter.

 

[dewexler]

Our delima got worse. The 80A GFI's trip at 30ma. They are different, so, swaping is out. Out past the 3rd GFI is a chiller with it's own 50A GFI and has begun tripping. But leaves the tool still powered up. We have replaced the noise filter and suffered 1 trip of the 2nd GFI(orig prob.) while electricians messing with chiller. My question is: Can GFI in series like this, the up stream GFY trip without the down stream tripping? Now, with the chiller issue, i think i have multiple issues. We got hit with lightening last week, and this was one of 4 tools taken out. Colorado Springs, home of M. Tesla.