question

mitchweld avatar image
mitchweld asked

wiring two paralleled 120v only inverter generators to 100 amp victron autoformer to feed home panel

split phase
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2 Answers
Kevin Windrem avatar image
Kevin Windrem answered ·

You might want to consult an electrician to make sure things are done correctly. That said, creating 120/240 split phase from 120 volt single leg might not be something all electricians would be familiar with.

Fron your description it sounds correct but again having first-hand advice could save you grief and danger in the future.

Back-feed breakers are dangerous. I assume by ”interlocked” you mean that you can’t turn on the generator breaker until the main is turned off. If not, you really should make that happen. Turning o the main and generator breakers at the same time would destroy the generators and could also activate the high voltage wiring on the poles during a power outrage, resulting in injury or death of the line worker!!!!!!

You should also make sure the inlet to the house is a MALE connection with the female on the cord end. Otherwise, there’s a shock hazzard if the cord gets disconnected while the generator is running. I see far too many male-male cords made to back-feed a generator into existing electrical breaker boxes. It’s just not safe.

The paralleled generator output could exceed the 50-amp rating of your wiring and connectors. You should probably install a 50 amp breaker at the generator to avoid overloads and melted wiring/connectors. Or you could place the autotransformer at the generator before connections to the house. Then the 14-50 would have appropriate currents. A 6-50 might still be overloaded so that should probably change.

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shaneyake avatar image
shaneyake answered ·

First thing, support is meant to come from the dealer that should you the autotransformer. You should give them a call if you need support ASAP.

Are the 2 generators able to be synchronized? Both in phase or 180 degrees out of phase?
If they can't be synchronized they can't be used together. If they can be synced 180 degrees out of phase then you don't need the autotransformer unless you are trying to use it to balance the phases.

if they can only be synchronized in phase then you will parallel them first and then use the transformer to create 240V with 120V passthrough. This is limited to 28A on the second leg, which includes 120v and 240v loads that use L2.

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Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.