Installing an Inverter-Circuit Breaker Size an Location?

PerryB67

New Member
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
 

rmaddy

Solar Addict
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.
 

PerryB67

New Member
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
 

chrisski

Photon Sorcerer
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.
 

Hedges

I See Electromagnetic Fields!
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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rmaddy

Solar Addict
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.
 

Hedges

I See Electromagnetic Fields!

PerryB67

New Member

Hedges

I See Electromagnetic Fields!
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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