question

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cord asked

Breaker size for 12/800 inverter?

Off grid power system for a small cabin. Primary power will be provided by a generator that will feed into the breaker panel main. When on solar, I'll need to turn the main breaker off and activate a circuit breaker. This will be controlled by a generator interlock kit that won't allow both breakers to be on simultaneously. I'd like to take 220v (2 @ 110v) power from the inverter and use each leg to feed through a two pole breaker. This will supply power to all circuits in the panel, even though the inverter is not capable of supply anything close to that level of power. What size breaker should I select to pass the power through? I believe a 10amp breaker might be the smallest one I can get. Should I install a smaller breaker to protect the inverter or is it protected internally? I can't figure out how to get 220v two pole power from the inverter, the data sheet says it's capable of 220v power, but the manual doesn't mention it. Is there something I'm missing?

Phoenix Inverter
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1 Answer
wkirby avatar image
wkirby answered ·

The circuit breakers are there to protect the wiring, so select an appropriately sized circuit breaker for your wire size.

This inverter on its own can be configured to output 220V, but it is not two pole.
For two pole you'll need to use an Autotransformer on the output which can then create two 110V legs with a neutral in the centre. There are Victron Autotransformers, but they are large and overkill for a small inverter like yours. Perhaps you could source a smaller one from a local electrical factors in your area. Make sure that you configure the neutral-Earth link as appropriate. Consult your electrician if you are not sure what this is or how to configure it.

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