# Residential 400a. Service Both Main Tripping



## Podagrower (Mar 16, 2008)

I have lots of ideas, but my wife says to keep them to myself. As for your problem, Things that jump out at me would be-
1. Make sure power on line side of meter is stable.
2. Loose nuetral, this can make you nuts.
3. Other loose connection, or plastic coating on aluminim wire (or other debris)
4. On the panel with fluctuating voltage, if the surge arrestor didn't already puke, check votage with it disconected.

I would be a little surprised for a short between the meter and main to trip the main, are you sure there are no problems downline?


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## randomkiller (Sep 28, 2007)

I would break out the megger and make sure you don't have a simple cable insulation problem or short after checking all the lugs for a loose connection. Not all that far back I had come across a disconnect that the set screws were tight in the sockets but not to the wires, like the set screws were the wrong thread.


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## micromind (Aug 11, 2007)

I would not turn either main back on without meggering the feeders. Breakers usually trip for a reason, if you close them into a fault, it could make a big bang. Not worth it when a megger test is so simple. 

Rob


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