Inverter Adder Advice - 2025 Hideout 31BRD

Additionally, the transformer in a 3000 watt inverter uses more energy to power the primary winding in the transformer than a 2000 watt inverter which uses more battery power to excite the primary winding than a 1500 watt inverter consumes... in other words, the bigger the inverter, the more battery power it will use to provide the output wattage you intend to consume.

Sort of like a Ford 7.3L gas engine will consume more gas at idle than a Ford 1.5l gas engine at idle. Inverters are "sort of the same"... The power flowing through the inverter primary winding will be greater (use more battery power) the larger the inverter rating.
 
Instead of a fuse on the hot wire from the battery to the inverter you might want to think about using a DC circuit breaker. In the (hopefully) rare event the fuse blows you would a) have to have a spare and b) replace it.

DC Circuit Breaker

There are other models by other vendors.
I'll be adding a breaker to the circuit as well.

The fuse is for the hot to the inverter.
 
Did a lot of poking around, bit the bullet and ordered the 3000w pure sine Renogy inverter with built in ATS, external controller, and overload protection.

Finally wired it up, works great. Still think it's stupid how Keystone didn't add the bunkhouse TV to the inverter loop. Oh well.

I'm planning to run 2x 325w solar panels onto a mppt 150/85 charge controller next. Currently the 220w solar panel w/ mppt 100/30 controller likely won't keep up.

The goal is to run TVs, coffee maker, starlink overnight and charge during the day (generator, shore, and/or solar)

Currently have it under a load test to truly understand the draws and needs before it gets too warm out and I reconnect to shore.
 

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In the previous post you stated "load test". I would monitor these cables as they sound too small for a 3000W inverter that probably is rated that at continuous output (vs peak). Is that what their installation/user manual recommended?
 
So how did you decide on that size?

1/0 AWG wire at 12 volts is rated for 120 amps which is 1440 watts.

To get 3000 watts out of your (oversized) inverter you need 3000 watts (plus conversion loss) input. 3000 watts / 12 volts = 250 amps more than double that that of the rating of 1/0 AWG.

Additionally, 3000 watts A/C output is (assuming 120 volts nominal) will produce 25 Amps which is more than what the 12 AWG (yellow Romex) is rated for. There is no overcurrent protection (circuit breaker) on the 12-wire when you are using the battery and Inverter to generate A/C power.

Current is what dictates AWG. Overcurrent equals overload circuits which is a safety concern.

You may want to rethink your installation.
 
By "load test" I meant testing using it under load.

The cable size was recommended by their manual. Yes.

Also I have a 30amp breaker on the roomex side.
 
By "load test" I meant testing using it under load.

The cable size was recommended by their manual. Yes.

Also I have a 30amp breaker on the roomex side.
If you have placed a 30 amp breaker on the ROMEX side on 12 gauge (yellow) ROMEX, then you're not adequately protecting that wiring circuit. The MAXIMUM rating for 12 gauge ROMEX is 20 amps.
 
The appropriate size cable for a 2,000w inverter is 2/0 so I don't know how 1/0 can possibly be safe for a 3,000w inverter. Length of the wire run between the inverter and the battery is a factor, and most people neglect to take into consideration that the length includes both positive and negative.

For example, an inverter that is 10 feet away from the battery needs to factor 20 feet of cable, and for 20 feet using a 3,000w inverter, you need 2/0 if not 3/0 cable.

That setup should not have a 3,000w inverter because the Romex can't handle it, and the power cables you used are too small. Trusting a breaker to be your safety when you know you are going to easily overload a circuit is a very bad idea. I can't tell what size fuse you have, but it should be 250A. Although Renogy is a well known brand, their inverter function is still lacking modern functions. For example, the inverter has to be powered on 100% of the time, even while on shore power because while it does have an auto transfer switch, it does not have power passthrough. Inverter off or dead, and all your downstream inverted outlets are dead too. Not to mention that a 3,000w inverter at idle consumes more battery energy than a smaller one.

Anyway, best of luck with your setup, I hope it works out.
 
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If you have placed a 30 amp breaker on the ROMEX side on 12 gauge (yellow) ROMEX, then you're not adequately protecting that wiring circuit. The MAXIMUM rating for 12 gauge ROMEX is 20 amps.
12/2 Romex is rated for up to 20amps correct, in a constant manner, it doesn't mean it can't handle a surge of more, it's often used in 120v/20amp circuits. Yes, it may heat up if continuously run at 20+ amps.

FYI a 30amp circuit breaker will trip at 24amps. I've also added a 20amp Fuse after the breaker as a "failsafe" the AC output is setup as a 20amp 120v circuit.

The appropriate size cable for a 2,000w inverter is 2/0 so I don't know how 1/0 can possibly be safe for a 3,000w inverter. Length of the wire run between the inverter and the battery is a factor, and most people neglect to take into consideration that the length includes both positive and negative.

For example, an inverter that is 10 feet away from the battery needs to factor 20 feet of cable, and for 20 feet using a 3,000w inverter, you need 2/0 if not 3/0 cable.

That setup should not have a 3,000w inverter because the Romex can't handle it, and the power cables you used are too small. Trusting a breaker to be your safety when you know you are going to easily overload a circuit is a very bad idea. I can't tell what size fuse you have, but it should be 250A. Although Renogy is a well known brand, their inverter function is still lacking modern functions. For example, the inverter has to be powered on 100% of the time, even while on shore power because while it does have an auto transfer switch, it does not have power passthrough. Inverter off or dead, and all your inverted outlets are dead too.
The romex only sees 20-24amps. Renogy's newest 3000w Pure Sine Inverter w/ built in ATS and Overcharge protection does have power passthrough when connecting shore power, it can stay on all the time or only partial the time. I'm only using the inverter as overnight available power in case of shore power going down or being unavailable. Yes the 3000w inverter is overkill.

My setup is +/- 6ft from the battery. 1/0 AWG is rated up to 350amps (not recommended obviously) at consistent current draw, the Renogy manual recommends a 400amp fuse. I have downsized it to 200amps with spare 200s, 250s, and 350 ANLs available.

ALL of this is redundant, as the dealer shared the wiring diagram of my trailer. The "inverter ready loop" already goes through the breaker box and a 20amp circuit breaker on the AC of the breaker box to the first GFCI receptacle prior to the other 6 receptacles. IE that circuit is only currently powered when shore is connected. This was confirmed by a trusted local electrical.
 
Since you've thoroughly researched this and can quote the ampacity at which a 30 amp breaker will trip (24 amps) and have installed your system to meet your requirements, all I'll say at this point is, "Happy Camping" ....
 
By "load test" I meant testing using it under load.

The cable size was recommended by their manual. Yes.

Also I have a 30amp breaker on the roomex side.
That would be the first time I've every seen a 3000W inverter manual that recommends a 1/0 cable. I would double check the wording/chart. Sometimes they write a common manual for a 1000W/2000W/3000W inverter series and the have footnotes or charts that change the cable specification. Minimally I would expect 2/0 cables even with the downgraded (lower) fusing you have installed and that includes the jumpers between the batteries in the battery bank.

Your not going to run into a problem with the coffee maker running and people watching TV but then someone plugs in the curling iron and blow dries their hair then you might will see something happen
 

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