diy solar

diy solar

Inverter parallel wiring, is there a reason I can't do this?

Rednecktek

Solar Wizard
Joined
Sep 8, 2021
Messages
5,444
Location
On a boat usually.
So here on the ship we don't run 1 AWGinormous wire from the generator to the main switchboard, we break it up into 6 smaller wires bolted to each lug on either end. This is to make it physically possible to run that much power and still bend wires without putting so much amperage through them that they melt.

I'm looking at putting in a small solar setup for the new storage shed and the new garden shed. I already have some panels, a 40a MPPT controller, going to put in some 24v battery love, all I need is the inverter.

I was thinking about putting in a 2500-ish watt inverter and connecting it to a small breaker panel to feed out to the 4 circuits (15a lighting, 20a outlet, 2 buildings) but while the inverter says it can pump out 2500w all day and surge up to 4000-ish, it only comes with a few 15a outlets and drawing that much power across them would involve fire and an unhappy wife.

So here's my thought. Can I take 3 or 4 male plugs and wire all the Hot leads to the breaker panel and all the Neutral leads to the N-bus and spread the amperage load across multiple outlets on the inverter? Mathematically this would let me draw all the amperage the inverter can provide without cooking anything off.

I just don't know if there's some sort of harmonic frequency black magic or circuitry weirdness that would make this a "Bad Idea" or anything like that.

So, is there any reason I can't do this? (Forgive the krappy MSPaint drawing. :) )
 

Attachments

  • inverter-wiring.jpg
    inverter-wiring.jpg
    45.8 KB · Views: 14
What you are asking can be done and I have actually done it on mine but, it is not necessarily safe. The reason being that if you pull out one plug out of the inverter the others are still plugged in, the one that you pulled out is energized because it is tied into the others in your combiner box. So if you touch the unplugged one, it will shock you. So it can be done but it is not really safe especially if you have kids around that get inquisitive.
 

Attachments

  • 20201126_093443.jpg
    20201126_093443.jpg
    68.2 KB · Views: 27
Fortunately all my kids meow and demand wet food, so no worries there. This is all going to be mounted up in the loft so it's not like anyone will be able to get to it without a ladder.

Good to know there wasn't some weirdness I was unaware of.
 
No sir, not possible. Just feeding 5 - 110 circuits each off of two different inverters. It just looks I am doing that. I am actually in the process of buying a 220 inverter to actually have a split phase setup.
 
2500W is less than 2 120v 20A outlets are rated for...
120x20 is 2400W on a single outlet...
 
Yes, I realize the breakers are oversized but that's what's available in stores. The reason I'm splitting the circuits is because it's a huge pet peeve of mine to have lights and outlets on the same wire. If I need to work on an outlet I want to turn on the light so I can see what I'm doing. If I'm working on a light I want to plug in a lamp.

Since all the wiring is going to be bog standard Romex and breakers I can buy at Lowes I'm just going to use the 15a and 20a breakers for the 14AWG and 12AWG wiring. If I upgrade later or someone decides to trench out and run a line from the main house, the panel and wiring will already be up to snuff.
 
Why not just use 3 small breaker boxes and run a wire to each breaker then just run 14g for lites and 12g for outlets
you can use the 3rd plug for whatever you want ?
it would be better to have a inverter that can be hot wired with out plugs .?‍♂️
 
Why not just use 3 small breaker boxes and run a wire to each breaker then just run 14g for lites and 12g for outlets
you can use the 3rd plug for whatever you want ?
it would be better to have a inverter that can be hot wired with out plugs .?‍♂️
That’s what I was thinking, but aren‘t the inverters outlets protected by onboard over current protection already. Granted if it is in an inaccessible location you may want to put lower current protection in a more accessible place, but protecting a 15 amp outlet with a 20 amp breaker downstream of it doesn’t seem effective to me

that being said I am learning, and may well be missing things. Please help me understand

thanks
 
that being said I am learning, and may well be missing things. Please help me understand

No, it sounds odd to have multiple breakers higher than the source amperage can supply, I'm just doing it that way for a few reasons:

1: This system will be powering 2 sheds, a storage shed and a garden shed, hence 4 breakers.
2: The sub panel and breakers (15a, 20a) are cheap and available at Lowes, so I might as well use what's available.
3: I FU#$(ING HATE with an UNHOLY PASSION having lighting and outlet circuits on the same breaker. It limits the outlets and if I want to work on a light fixture I can't plug in a lamp. Likewise if I need to replace an outlet I can't turn on the lights. Drives me bat Sh1T CRAZY!!!!
4: There's a chance I might actually trench and run a real supply wire down there someday so I'd like to have my options open.

A 2500w inverter would be about perfect. Way overkill for the load 90% of the time but available when I really need to plug something in and don't want to walk up that steep ass hill to do it. :)
 
I use a 3600 watt inverter and I have 15 and 20 amp breakers 39 of them in a 200 amp panel .
It’s funny some times a breaker pops in the panel some times it the breaker on the inverter system .
It works fine.
My 200 amp breaker just acts as a switch .
I need to have a Service panel for inspection anyway
 
I believe the breakers on most inverters are 15amp so they will /could pop .
Most loads are small I run on 2/300watt less at nite .
But I still need extra power for microwave
Toaster or what ever , washer and dry could be nice to run at the same time with some lites and radio then the frig and stand up freezer .
 
For whatever it’s worth, breakers are designed to protect wire. If you have a 20 amp circuit, the wiring for that circuit needs to support a 20amp workload. They are to keep things from catching on fire.

if you overload a system, then there needs to be sufficient disconnects to protect wires from getting hot.
 
Back
Top