Wiring from 12v Batteries to Converter in Casita

[cozygirl]

After reading Handy Bob we want to hook up the 2 golf cart batteries and run to the back of the Casita to the converter. It was recommended to use #2 battery cable. the distance is 15 feet. Can't find the wire anywhere...or is there another option to hook the converter up? Is a 2/O or 4/O wire heavy enough to carry the voltage that distance?

[David B.]

Originally Posted by cozygirl

After reading Handy Bob we want to hook up the 2 golf cart batteries and run to the back of the Casita to the converter. It was recommended to use #2 battery cable. the distance is 15 feet. Can't find the wire anywhere...or is there another option to hook the converter up? Is a 2/O or 4/O wire heavy enough to carry the voltage that distance?

Our local NAPA auto parts store makes custom wire by the foot, and crimps any style ends on it that you would like.

[Eddie Longest]

Marine stores usually have a good selection of wires but you have to watch the price.
Eddie

[cozygirl]

Is 2/O the way to go?

[mary and bob]

2/0 should be plenty big. Is this wire to power some 12 volt lights and recharge the battery? Look at big trucks, they don't use that heavy a wire off a 80 amp alternator. Unless you are powering a 12 volt starter or liftgate motor, 2/0 is way oversize.

[cozygirl]

We are running two 2volt batteries that we box on the front hitch to the converter - so does the 15ft distance matter on wire guage?

[Thomas G.]

Originally Posted by cozygirl

We are running two 2volt batteries that we box on the front hitch to the converter - so does the 15ft distance matter on wire gauge?

Do you mean converter or inverter? If you don't know the difference we need to restart the conversation, as it makes a huge difference.

[cozygirl]

Running the wire under the camper from 2 12volt batteries on trailer hitch to the back converter.

[hotfishtacos]

Originally Posted by Thomas G.

Do you mean converter or inverter? If you don't know the difference we need to restart the conversation, as it makes a huge difference.

Yes it does! Inverters require large diameter wires to handle the large amp draws under worst-case conditions. I ran 3 gauge wire about 6 feet to my 2500 watt inverter as required in my owner's manual.

On the other hand, converters require much smaller wiring because they just keep the batteries charged while you are plugged in and sometimes provide the feed-wire from the battery to the trailer distribution panel. This wire from my batteries to the converter is I believe 10 or 12 gauge...no bigger.

Good luck!

[cozygirl]

Thomas,
I guess the #2 battery cable wire will be sufficient enough then?

[Thomas G.]

Originally Posted by cozygirl

Thomas,
I guess the #2 battery cable wire will be sufficient enough then?

It depends. Inverter or converter?

[David Tilston]

2/0 would be good for a big inverter.

[Thomas G.]

Originally Posted by David Tilston

2/0 would be good for a big inverter.

And if it is a converter, total overkill.

[Jared J]

This is what you need to look at.

http://www.engineeringtoolbox.com/am...uge-d_730.html

You need to know the distance between your battery and converter, and converter amp output. I highly doubt 10 gauge is close to ok. With my new converter, I got 4 gauge wire from Greg's marine wire supply online. Remember, if you battery is fairly low, you can have a lot of current going to it.

I emailed progressive dynamics about it:

"Yes the wire should be rated for the full amperage of the converter and fuse (which should be close to the battery to protect the wire) whichever is higher.

I cannot recomend wire sizes due to liability issues.

Wires should be sized according to the RVIA / NEC codes.

For a rough guide see:
http://www.powerstream.com/Wire_Size.htm?nowritefs for voltage drops using different
gauges verses distance/load


Service Department
Progressive Dynamics"

P.S. 2/0 or 4/0 is much larger than the 2 gauge you mentioned. It starts with the higher the number, the thinner the wire. When you hit 0 and go to the x/0 sizes, the larger the number, the bigger.

[rabbit]

I'm running about the same distance to a PD9245 converter with 6awg welding cable. I have a 4' run of 1/0 to a 1500/2000watt inverter.

jack

[Thomas G.]

Originally Posted by rabbit

I'm running about the same distance to a PD9245 converter with 6awg welding cable. I have a 4' run of 1/0 to a 1500/2000watt inverter.

jack

The OP won't say if it is an inverter or a converter, nor give any indication of the expected current to be carried.

[steve dunham]

Go to a welding supply shop and get some welding lead. They have wire sizes #4 AWG to 3/0 AWG. The wire has a tough insulation and has extremely fine strands giving it great flexibility . Standard 3/0 building wire is not very flexible

[Jared J]

Originally Posted by Thomas G.

The OP won't say if it is an inverter or a converter, nor give any indication of the expected amp carried.

They said converter. You're right on amps, but that's what the chart is for. For my pd4045, which is 45 amps on 15', it was borderline 6-4 gauge, depending on the chart, so I erred on the safe side with 4 gauge.

[Jon Vermilye]

While not inexpensive, you can get either boat cable or welding cable from GenuineDealZ. The advantage is they will make up cables to length with your choice of color, terminals (complete with heat shrink) etc. I used them for my inverter cables & was happy with the quality of the work.

[David Tilston]

Originally Posted by Jared J

I cannot recomend wire sizes due to liability issues.

But being Canadian, I am less reluctant in this regard. According to this link
Ampacity of Copper & Aluminum Wire

It depends on how much heat you can tolerate, (insulation on the wire). At the lowest heat rating, you are good to 145A on 2/0. at 12VDC, this represents 1740W. I would use this on a 1500W inverter. The highest temperature rating gets you 195A. At 12VDC that would be good for 2340W, or a 2000W inverter. 1/0 would just barely work for a 2000W inverter if the wire was rated to 90°C, the highest rating. A 3000W inverter would require 4/0, high temp wire.
The longer the wire the higher the voltage loss, so keep your runs as short as possible on an inverter.