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Installing an Inverter-Circuit Breaker Size an Location?

PerryB67

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Have decided to install a GIANDEL 2200W Pure Sine Wave Power Inverter 12V DC to 110V 120V AC. This is one of Will Prowse's recommendations and is much bigger than we need (Yeah, right!). We don't and won't ever have a microwave, but want it for a 750 watt toaster and a 750 watt hair dryer for Terry. We have a Dickinson stovetop, so I doubt we'll ever have an induction stovetop.

I would disconnect the outlet below the kitchen countertop from the shore AC and wire this outlet to the inverter. We're boondockers and this shore power outlet is essentially worthless anyway.

I already have a perfect spot for the inverter, it will be less than 2 feet from the batteries, protected from moving items, and will have plenty of air space around the inverter for cooling. I will be purchasing new 2 awg cables for both positive and negative.

We have a Victron Smart 712 BMV already installed. Current plan is to connect the inverter to the negative input side of the shunt with a 2 awg cable and have a new 2 awg cable from the shunt to the battery. Correct me if this is incorrect.

I would install a Bussman circuit breaker with shutoff on the positive cable.
What size breaker should I purchase? 25 or 35 amp? Larger than 35 amp?

Should I install another Bussman circuit breaker on the negative side or is that just foolish redundancy?

Thanks,

Perry
 
2200W / 12V = 183A. That needs 2/0AWG wire, not 2AWG wire. And you'll want a 250A fuse or breaker. You have a 2200W inverter. You should wire for it. Don't assume you'll only ever use a small amount of it. If you only need 1000W then buy a 1000W inverter. It would be cheaper for the smaller inverter and cheaper for the smaller wire and fuses/breakers.

All wires between the batteries and inverter and all components in between (shunt. fuses) need to be the same 2/0AWG wire.

The input of the shunt goes to the battery negative. Everything else connects to the other end (non-battery) of the shunt. The inverter fuse should go on the positive wire.

If you have multiple things that need to be connected to the battery you should probably make use of bus bars.
 
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2200W / 12V = 183A. That needs 2/0AWG wire, not 2AWG wire. And you'll want a 250A fuse or breaker. You have a 2200W inverter. You should wire for it. Don't assume you'll only ever use a small amount of it. If you only need 1000W then buy a 1000W inverter. It would be cheaper for the smaller inverter and cheaper for the smaller wire and fuses/breakers.

All wires between the batteries and inverter and all components in between (shunt. fuses) need to be the same 2/0AWG wire.

The input of the shunt goes to the battery negative. Everything else connects to the other end (non-battery) of the shunt. The inverter fuse should go on the positive wire.

If you have multiple things that need to be connected to the battery you should probably make use of bus bars.
Oops! I meant 2/0 AWG.

250A breaker it is. This Bussman 250 amp breaker should be adequate.

Yes, I forgot to mention bus bars are used, but I have a feeling new buss bars will be needed for 2/0 awg wires.

Thanks,

Perry
 
I would disconnect the outlet below the kitchen countertop from the shore AC and wire this outlet to the inverter. We're boondockers and this shore power outlet is essentially worthless anyway.
Now, I hook my inverter with a 15 amp extension cord to my shore power. This lets me go back to shore power if needed, like to charge on a cloudy day. I don't like the idea of my power source being on the wrong side of my breakers. I also don't like the idea of someone down the road borrowing the RV or buying the RV and with good intentions plugs to shore power.
Yes, I forgot to mention bus bars are used, but I have a feeling new buss bars will be needed for 2/0 awg wires.
I found this was an issue after the cheap 250 amp brass busbar I purchased off Amazon would not fit 5/16th inch lugs with my 4/0 wire I had planned.
We have a Victron Smart 712 BMV already installed. Current plan is to connect the inverter to the negative input side of the shunt with a 2 awg cable and have a new 2 awg cable from the shunt to the battery. Correct me if this is incorrect.

After the shunt for me comes a busbar with studs for where the SCCs come in; the Inverter is, The RV 12 volt power goes to; and whatever your cloudy day charging device of choice is.
 
2200W/10V/90% efficiency = 245A (at low voltage cutout, and guess of inverter efficiency.)
245A x 1.25 = 306 (avoid nuisance trips)
306 x 1.12 = 342 (60 Hz ripple current drawn from battery causes 12% more heating than DC delivering same power)

So I would say 350A fuse, and wire sized for it.

Ain't it fun designing for 12V?
 
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2000W/10V/90% efficiency = 245A (at low voltage cutout, and guess of inverter efficiency.)
The OP actually has 2200W. I never factor as low as 10V. In my own 24V system my inverter is setup to shutdown at 24.0V because I'd rather save power for my DC stuff such as the fridge and lights. If I were to let the inverter take my batteries down to 20V my milk would go bad.
 
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Not that I'm recommending it; I think you should have 350A breaker, not 200A

Your battery's data sheet says "internal resistance < 2 milliohm"


6V/0.002ohm = 3000A short-circuit current, which does fit within that breaker's AIC capability.


250A breaker



An alternative is a switch + fuse


This line of fuses goes up to 300A. Could be most economical solution that would probably carry all the current you might draw.



Class T 350A. This interrupt 20,000A so good for lithium too


 
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I dont mean to hi-Jack this thread but have noticed many threads on this very topic regarding the 400 watt post by will. I, like the OP have a very similar set up. I have a Renogy dc to dc 50. 400 watts of solar. And two 100 ah batteries.
Could a member possibly advise on the following...
Can I install a 250 amp circuit breaker going to the inverter ( circled on photo) I will be using 2/0 to the battery, fuse box, inverter etc. Is it advisable to install a 350 amp anl or T glass fuse inline before the shunt. My neighbor advised me on this. Any help would be appreciated.20220402_043351.jpg
 
I dont mean to hi-Jack this thread but have noticed many threads on this very topic regarding the 400 watt post by will. I, like the OP have a very similar set up. I have a Renogy dc to dc 50. 400 watts of solar. And two 100 ah batteries.
Could a member possibly advise on the following...
Can I install a 250 amp circuit breaker going to the inverter ( circled on photo) I will be using 2/0 to the battery, fuse box, inverter etc.
You can install a circuit breaker there, but what size is the inverter? Also, make sure it’s a quality DC fuse
Is it advisable to install a 350 amp anl or T glass fuse inline before the shunt. My neighbor advised me on this. Any help would be appreciated.
On a negative grounded system, install a fuse on the positive side as close as possible to a battery. Class t for lithium; ANL for lead acid.

If you use chassis ground, potential could be there for a fuse to blow but the current flow through the chassis ground if the shunt is on the negative side. My shunts say to mount on the negative side first thing after a battery.
 
In USA dc systems we do not fuse the negative. There must be a fuse at each battery bank's positive terminal. There must be a fuse at each following connection where a positive wire changes size (gauge).
 
Thanks for your response! The inverter is 2200w. Have have indeed grounded to the chassis. The batteries are lithium. I noticed there is a entire thread dedicated to Will's review of the 400 watt DC to DC charger. I'm new to the forum and am just finding my feet. I appreciate your advice.
 
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