Wiring inverters to breaker box (off grid)

Flip

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Forgive me if this has been discussed, but everything I found was for grid tied systems. I'm looking advice on wiring an AC breaker box from my inverters. I'm off grid and have 2 inverters (different brands and sizes).
My initial thought was to power half of the breaker box with one inverter and power the other half with the other inverter. To do this I'd have to combine neutrals which I wasn't sure would be healthy for the inverters.
My second thought was to power 2 smaller breaker boxes, one for each inverter. I could power both sides of the box from the same inverter. I would still have to combine neutrals, but at least it's from the same source. I'm still not sure if that's ok or not.
Any other ideas? Thoughts on these options? Thanks in advance for your help.
 

12VoltInstalls

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second thought was to power 2 smaller breaker boxes, one for each inverter. I could power both sides of the box from the same inverter. I would still have to combine neutrals, but at least it's from the same source. I'm still not sure if that's ok or not.
Any other ideas? Thoughts on these options?
Some inverters on the high end I believe are stackable. MPP Solar I believe has smaller single phase AIOs that can use an optional device to make split phase. Plus there’s a number of split phase AIOs available.
Barring equipment that can be made to do split phase or combined in an approved manner you can feed both legs of the panel with the same inverter provided no split-phase or double breakers are required.

If you haven’t bought the breaker box you can just buy a 120VAC subpanel
 

Flip

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Some inverters on the high end I believe are stackable. MPP Solar I believe has smaller single phase AIOs that can use an optional device to make split phase. Plus there’s a number of split phase AIOs available.
Barring equipment that can be made to do split phase or combined in an approved manner you can feed both legs of the panel with the same inverter provided no split-phase or double breakers are required.

If you haven’t bought the breaker box you can just buy a 120VAC subpanel
Thanks! I don't have a need for double pole breakers. I did figure that would a problem. So just to confirm, without buying different and/or additional equipment, you suggest I run 2 boxes (one for each inverter), power both sides of the box and neutrals combined from the same inverter is ok. Correct?
 

WYtreasure

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I vote for 2 small breaker boxes, $15 to $20 + breakers. There will be NO combining of neutrals as long as you don't cross the circuits somewhere downstream.
A double pole box does not have to be something you avoid. Power both poles from the same inverter, just jump the hot from one pole to the other OR just use half the box.

Edited the "NOT SO SMART" part, thanks MichaelK.
 
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Flip

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I vote for 2 small breaker boxes, $15 to $20 + breakers. There will be NO combining of neutrals as long as you don't cross the circuits somewhere downstream.
A double pole box does not have to be something you avoid. Power both poles from the same inverter, just jump the hot from one pole to the other OR just use half the box.
I also thought about jumping the hot over, but then I thought.....I have 2 outlets on the inverter. I can can just run a pig tail (cut off extension cord) from each outlet to the box and power both sides without a jumper. But then I'd have 2 hot, 2 neutral and 2 ground. That's what I meant by combining neutrals from the same source/inverter.
 

timselectric

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I also thought about jumping the hot over, but then I thought.....I have 2 outlets on the inverter. I can can just run a pig tail (cut off extension cord) from each outlet to the box and power both sides without a jumper. But then I'd have 2 hot, 2 neutral and 2 ground. That's what I meant by combining neutrals from the same source/inverter.
If they only have receptacles and no hard wire connections. The receptacles are probably feed from one circuit. Probably only need to plug into one and feed the panel.
 

Wellbuilt

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I just use one 3600/48 inverter
I have a large panel 40 spaces and I just jumped the l1l2 together
my panel is full .
if you have a 3000watt inverter i would just use one and see how it go’s .
My cabin is 2800sf and runs on 2/300watts most of the time
maybe add the 2000watt inverter for a heavy load that is not used much so it can be off for most of the time
i would use a 2 pole panel so you can get one inverter in the future
 

Flip

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If they only have receptacles and no hard wire connections. The receptacles are probably feed from one circuit. Probably only need to plug into one and feed the panel.
Agreed, but I know 2 hot or neutral under one lug is a no no. So I was trying to figure out to avoid the jumper. But then I end up with 2 neutrals. 🤷‍♂️
 

12VoltInstalls

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So basically under 30A at 120 or 250A from batteries, max at 12.8 for the 3000W Smokeshow Klassic inverter.
Why not get an RV panel that has the 12V fusing and 120V distribution and not think any further?
Agreed, but I know 2 hot or neutral under one lug is a no no. So I was trying to figure out to avoid the jumper. But then I end up with 2 neutrals.
🤷‍♂️
That’s electrically one neutral and you should affirm whether or not they are neutral-ground bonded in the inverter

If not they should be at/in the distribution panel
 

Flip

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So basically under 30A at 120 or 250A from batteries, max at 12.8 for the 3000W Smokeshow Klassic inverter.
Why not get an RV panel that has the 12V fusing and 120V distribution and not think any further?

That’s electrically one neutral
I haven't looked into RV panels. I do have a marine style fuse panel to run DC loads. Would be a clean install to have em all in the same panel. Well, 2 panels. I'll check that out. Thanks.
 

timselectric

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With small portable inverters you have to be careful with n/g bonding. Especially when the DC negative is grounded to the inverter shell. They tend to release their magic smoke.
 

Flip

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With small portable inverters you have to be careful with n/g bonding. Especially when the DC negative is grounded to the inverter shell. They tend to release their magic smoke.
Thanks. I was planning on going with sub panels vs main for that reason. Keep everything separate in the panels and run one ground out back to the ground bus bar in my main panel.
 

timselectric

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The problem is that without a n/g bond. You will have no short to ground protection. With a floating ground, you basically have no ground.
 

MichaelK

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A double pole box does not have to be something you avoid. Power both poles from the same inverter, just jump the hot from one pole to the other OR just use half the box.
You have to be very careful here. The whole purpose for utilizing a dual-pole breaker is to supply 240VAC to a load. With split-phase AC, the two 120V legs, L1 and L2, are 180degrees out of phase with each other. L1 to N is 120V. l2 to N is 120V. L1 to L2 is 240V. So, jumpering L1 to L2 makes the power single phase. You may know this, be the next person coming after you may not. Better to leave this fool-proof.
 
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