Growatt and MPP gave different answers

timselectric

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FYI: the input and output ground terminals, in the inverter. Are for chasis grounding, and carrying the ground on through to the loads.
 

MT off grid

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I am a licensed Electrician.
Yes
Yes
Yes
All grounds MUST be connected together.
Thats what I was thinking, just wasn't sure if I should use panel ground or separate earth ground if I made it put to be a solar generator with no ties to my house
 

timselectric

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Thats what I was thinking, just wasn't sure if I should use panel ground or separate earth ground if I made it put to be a solar generator with no ties to my house
It's connected to your house, as soon as you plug the cords in.
 

MT off grid

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It's connected to your house, as soon as you plug the cords in.
I'm so terrible at explaining things, so if I wired it to a transfer switch to my house I would use my house ground through the transfer switch, but if I build it as a power source that has no connection to my house I would need a ground rod separate from my house ground? Was thinking that I could get a small breaker panel and some 15 amp breakers and wire some outlets to the panel and mount it all on some concrete board and just use cords to power appliances as needed
It's connected to your house, as soon as you plug the cords in.
 

timselectric

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I'm so terrible at explaining things, so if I wired it to a transfer switch to my house I would use my house ground through the transfer switch, but if I build it as a power source that has no connection to my house I would need a ground rod separate from my house ground? Was thinking that I could get a small breaker panel and some 15 amp breakers and wire some outlets to the panel and mount it all on some concrete board and just use cords to power appliances as needed
In that case, you can use a separate ground rod.
But, I would still connect it to the existing grounding system. Especially since, you will be running extention cords (which I wouldn't recommend), throughout the house.
 

MT off grid

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In that case, you can use a separate ground rod.
But, I would still connect it to the existing grounding system. Especially since, you will be running extention cords (which I wouldn't recommend), throughout the house.
My plan is hooking to the house but I might need to use cords until I get the transfer switch done, just want to get things running and update as I go.
 

mccljs

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If the inverter does not bond neutral and ground in both bypass and inverter modes, then it is a non-separately derived system and can be treated the same as a generator that does not bond neutral and ground.

This means

You should be able to use the Reliance transfer switch that I think you talked about in a different thread since it requires a source that does not have neutral and ground bonded. Your MWBCs will need to be connected to 240V breakers so you will need two inverters in parallel.

If you use the inverter completely standalone, wired to outlets and using extension cords, you will need to create a neutral-ground bond for ground fault clearing. The easiest way to do that is have a small panel with some breakers for your outlets and a neutral-ground bond in the panel. I am not sure in this case if you should connect the inverter to your house ground, a grounding rod, both, or neither since you are using it as a completely separate system (the same as a standalone generator).

It gets a little more complicated if you plug the AC input into a house outlet for charging but I think in that case, the inverter would be considered an appliance, like one of those BLUETTI power stations. Unfortunately, you may create an objectionable current path since you will have a N/G bond in your main panel and in your extension cord panel. You may want to use a standalone battery charger and not use the inverter AC inputs at all. Tim can probably advise better.
 

MT off grid

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If the inverter does not bond neutral and ground in both bypass and inverter modes, then it is a non-separately derived system and can be treated the same as a generator that does not bond neutral and ground.

This means

You should be able to use the Reliance transfer switch that I think you talked about in a different thread since it requires a source that does not have neutral and ground bonded. Your MWBCs will need to be connected to 240V breakers so you will need two inverters in parallel.

If you use the inverter completely standalone, wired to outlets and using extension cords, you will need to create a neutral-ground bond for ground fault clearing. The easiest way to do that is have a small panel with some breakers for your outlets and a neutral-ground bond in the panel. I am not sure in this case if you should connect the inverter to your house ground, a grounding rod, both, or neither since you are using it as a completely separate system (the same as a standalone generator).

It gets a little more complicated if you plug the AC input into a house outlet for charging but I think in that case, the inverter would be considered an appliance, like one of those BLUETTI power stations. Unfortunately, you may create an objectionable current path since you will have a N/G bond in your main panel and in your extension cord panel. You may want to use a standalone battery charger and not use the inverter AC inputs at all. Tim can probably advise better.
Thank you for taking time to be very detailed and easy to understand, I would like to use my transfer switch but like another member said, it has a bridged input and output neutral, im still reading and learning all of these fine details to electrical
 

timselectric

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Unfortunately, you may create an objectionable current path since you will have a N/G bond in your main panel and in your extension cord panel. You may want to use a standalone battery charger and not use the inverter AC inputs at all.
Absolutely correct.
 

timselectric

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Thank you for taking time to be very detailed and easy to understand, I would like to use my transfer switch but like another member said, it has a bridged input and output neutral, im still reading and learning all of these fine details to electrical
If you don't connect the inverter input to your house, you can absolutely use the transfer panel.
As long as it's a completely separate system. (Other than grounding)
 

mccljs

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Thank you for taking time to be very detailed and easy to understand, I would like to use my transfer switch but like another member said, it has a bridged input and output neutral, im still reading and learning all of these fine details to electrical
Bridged neutral only if you use AC input. If you use a separate charger, you don't need to worry about it.
 

MT off grid

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If you don't connect the inverter input to your house, you can absolutely use the transfer panel.
As long as it's a completely separate system. (Other than grounding)
But if I choose to use a whole house transfer switch I could use the AC input and be fine?
 
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