Growatt 12k wiring with chargeverter

[Swillish]

Hi all, I purchased the Growatt 12k from signature solar back in 2021 and used the wiring diagram from watts247. Everything looked like it was working fine, used for a little over a hundred days, used about 2600Mwh and a cell went bad. left the system sitting for 2 years, never got to replacing the cell. Finally replaced the cell last month and noticed the system wasn't working how it used to especially when I was charging from solar and the AC through inverter and started reading the forum, learned about the transformer issues, neutral grid imbalance, when using bypass/passthrough mode. Decided to go with the chargeverter as a solution for not having AC input from the grid.

My question is to still be able to use split phase

1. do I still wire neutral and ground from my main panel to load panel and neutral and ground to the growatt inverter (according to the diagram from watts247)
2. neutral and ground from main panel to load panel but no neutral to growatt inverter. still wire ground to inverter.
3. don't know if the inverter itself creates neutral for split phase, if it does, would it be neutral from inverter to load panel, ground to load panel and inverter from main panel.

chargeverter will turn on through contactor triggered by low voltage and just help the battery maintain loads til morning and solar kicks in.

Thank you for any input!

 

[Swillish]

Bump

 

[shopman]

The only place you bond neutral and ground together is in the main panel. The Growatt creates its own neutral from the center tap of the transformer so you'll be running that neutral all the way to the main panel where you'll connect it to the existing neutral/ground bond. You'll also want to run a ground from the inverter to your main panel and attach to the ground bus bar. Without knowing your exact setup these are generalized directions. Anything outside of the main panel is considered a sub panel where the neutral and ground are not to be bonded together.

As far as using the relay contacts in the inverter to control the Chargeverter, keep in mind that in order for that to work the inverter has to go into bypass mode, so if you don't have AC hooked up to the input of the inverter you'll go dark. I've implemented the same approach of not connecting the grid to the inverter because of the transformer and use Home Assistant to monitor the SOC from a shunt. When the SOC drops to my set level, an automation closes the contacts on a Shelly Plus 1 which in turn energizes an 80 amp contactor and turns on the Chargeverter. Once it hits my set charge SOC another automation turns off the Chargeverter.

 

[Swillish]

The only place you bond neutral and ground together is in the main panel. The Growatt creates its own neutral from the center tap of the transformer so you'll be running that neutral all the way to the main panel where you'll connect it to the existing neutral/ground bond. You'll also want to run a ground from the inverter to your main panel and attach to the ground bus bar. Without knowing your exact setup these are generalized directions. Anything outside of the main panel is considered a sub panel where the neutral and ground are not to be bonded together.

As far as using the relay contacts in the inverter to control the Chargeverter, keep in mind that in order for that to work the inverter has to go into bypass mode, so if you don't have AC hooked up to the input of the inverter you'll go dark. I've implemented the same approach of not connecting the grid to the inverter because of the transformer and use Home Assistant to monitor the SOC from a shunt. When the SOC drops to my set level, an automation closes the contacts on a Shelly Plus 1 which in turn energizes an 80 amp contactor and turns on the Chargeverter. Once it hits my set charge SOC another automation turns off the Chargeverter.

Like the video, I thought I was able to use the generator start contact to trigger a contactor without AC input into the inverter. What I was confused about was that I wouldn't need to use a autotransformer like the video? Because I could tie in neutral from my main panel right? Just wasn't sure the correct way to wire in neutral without having the transformer in the inverter problems. I would be using 240v AC from the main panel to power the chargeverter. If I can't use the relay contacts in the inverter, using Home Assistant sounds like a good idea for automation, probably will be better then the relay contacts. Thanks for the idea.