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Lenny Jacobs

On 12/07/2017 08:54, wrote:

My "suspicion" is any one , or possibly combination of 2, would cause
the problem. Still don't know exactly what amperage the branch
breakers are, but he has a 63 amp "sub-main" that trips. If he has 7.5
amp breakers (equivalent to 15 amp 120 volt) and he has 25 running an
average of 1/4 capacity, that is 46.875 amps. Say the other 4 are at 6
amps each, the main may trip,(70 amps) while shutting any 1 off may
keep it from tripping at 64. The "short" resistance in the 4 may not
be exactly the same - one may draw heavier than the other on a given
day (it IS a "random" fault) - so shutting all 4 off, then turning the
others on, it may be different combinations that work from day to day.

Well, I have about 10 lights, one water heater (about 30 gallon), one
ceiling fan, three refrigerators. When I turned on TV/DVD, used a
kettle, turned on A/C, used the range in the kitchen, the breaker was
not tripped. It would take a lot more than these to overload a 63A breaker.