Whole house generator only powers one sub-panel

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MountainRog

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I live in a mountainous area with a lot of snow that takes down power lines frequently. The last owners of the house installed a transfer switch and have a Honda EX 4500 generator that previously powered the entire house (100 Amp service) as long we were judicious about our usage while on generator power. The last two times we've lost power the generator only has powered one of the two sub panels. Both sub panels have QO Square D Surgebreakers (QO2175SB) on them. When we're on utility power, both surgebreakers' LED lights are green. When the transfer switch is set to generator power and generator is on, only one subpanel has power and the Square D green LED on that panel is on. There is no power to any of the breakers on the other subpanel and the Square D unit is unlit. Is it possible that the Square D is causing the issue or should I be looking elsewhere? Other suggestions?
 

wwhitney

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Square D is a manufacturer. The QO2175SB is not causing your problem; its light being unlit is a symptom of the subpanel not getting power. The reason that panel isn't getting power is upstream of the panel itself.

Cheers, Wayne
 

Jeff H Young

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maybe that half of generator isnt working? it must have 2 20 amp breakers and no juice going through one a bad cord bad breaker, could be pretty easy to figure out but Id start at the generator
 

LLigetfa

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Since the QO2175SB is a 3-wire breaker, if one leg were dead, I would expect both breakers to exhibit the same symptoms. That said, it is sage advice to start circuit tracing at the generator.
 

LLigetfa

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QO2175SB is not a breaker. It is an SPD that connects to both busses and the neutral bar.

Cheers, Wayne
I stand corrected. None the less, if one leg was dead, then both SPDs should exhibit the same symptom assuming both are wired to both legs.
 

Jeff H Young

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actually likely no problem at generator as his sub panel must be recieving 240... shouldnt be to hard to track down
 
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