Transfer Switch Connections with Inverter and Main

[Lima126]

I have a Growatt 5000 and their Autotransformer. I am wanting to power 120v circuits from my main panel via a Pro-Tran xfer switch. Not planning on powering 240v at this time. With the autotransformer, I have a neutral, L1, L2 coming from a “inverter/generator” breaker panel that I would connect to the Pro-Tran. My question is the neutral line from the autotransformer. Does that go to the neutral in the pro-Tran and then the Pro-Tran neutral goes to the main panel neutral bus bar? Or do I “float” the neutral since the circuits of the Pro-Tran are still bonded to the neutral at the main even when they are powered by the “generator” side? Thank you!

 

[timselectric]

Common neutral.
One N/G bond. (Existing at the main panel)

Does that go to the neutral in the pro-Tran and then the Pro-Tran neutral goes to the main panel neutral bus bar?

This

Or do I “float” the neutral since the circuits of the Pro-Tran are still bonded to the neutral at the main even when they are powered by the “generator” side? Thank you!

It's impossible to float a system that is connected to a bonded system. You need both neutrals, to use both systems.

 

[Lima126]

Great. Thank you!