Battery switch what guage of wire to use?

ibra0078 · 02-22-2018, 10:57 AM

I will be installing a battery switch on my rv and eventually will be installing 2x 6v batteries in series to replace my 12v. I know to use 2 gauge wires when connecting the batteries in series but what gauge will one use to connect to the battery switch?

Has people been making their own cables from using booster cables as in Canada cables can be pretty expensive.

Thanks

Vicr · 02-22-2018, 11:30 AM

We need some more information to answer your question.
What type of RV do you have?
Do you have an inverter?
What loads are on your inverter?
What gauge cables are on your batteries?
How far from the batteries will your switch be?

jlechmanik · 02-22-2018, 11:55 AM

If you mean a bettery switch located at or near the batteries on a TT, I went with the same gauge that the wires connecting to the battery had. In my case it was a short cable between the negative battery connector and the switch. Then connected the main ground wire to the switch. Added a foot or less of cable.

Now it you are talking about a longer wire or a different purpose then some math and measurements will be needed to pick the proper wire gauge...

ibra0078 · 02-22-2018, 12:17 PM

Yes I want to install a battery kill switch near the battery on the TT when I am not using the TT. Simply removing the negative feed on the battery, mounting the switch maybe on the battery box itself (TBD), connect that feed into the switch and the other end will run to the battery negative. It seems the stock wiring seems very thin to both the positive and negative.

VICR no inverter at this time

**Mustang65** · 02-22-2018, 12:22 PM

Quote:

Originally Posted by jlechmanik

If you mean a bettery switch located at or near the batteries on a TT, I went with the same gauge that the wires connecting to the battery had. In my case it was a short cable between the negative battery connector and the switch. Then connected the main ground wire to the switch. Added a foot or less of cable.

Now it you are talking about a longer wire or a different purpose then some math and measurements will be needed to pick the proper wire gauge...

2x
CONGRATULATIONS on the JAYCO!!!

...and WELCOME TO JOF!!! The members here are GREAT!!! There is a lot of GREAT information to be found here. I am sure that you will have information and pictures to share with us... so please do!!

The size battery cable you need is determined by what you are connecting to the 12VDC system. The 2 gauge should be just fine.

If you are planning on adding a 1000 or 1500 watt inverter that will not matter as the leads from the inverter should be connected (through a high amp fuse) directly to the battery, and not pass through the battery cutoff switch. High amp loads should only connect directly to the battery.

Don

Don

My Registry

RVing with SOLAR

GrumpyDad · 02-22-2018, 12:50 PM

The battery kill switch will handle the same current as the wires connecting the battery to the rest of the RV. Most people use that logic and just use the same wire gauge and do just fine. Others will do some calculations based on amperage/load and do just fine. Others just use honkin' thick wire and do just fine.

If you are the type who enjoys "engineering" a solution, start figuring out the highest load that wire could see. Otherwise just use the same wire gauge as the rest of the circuit.

PlayersZ28 · 02-22-2018, 01:29 PM

I used welder cable from Princess Auto for my connections. I got lugs and shrink from Amazon. I used a very large Phillips screw driver and a steel V-block to crimp the lugs on. I did solder one cable but that just makes a very thick copper bar out of the cable.

ibra0078 · 02-22-2018, 01:49 PM

Quote:

Originally Posted by PlayersZ28

I used welder cable from Princess Auto for my connections. I got lugs and shrink from Amazon. I used a very large Phillips screw driver and a steel V-block to crimp the lugs on. I did solder one cable but that just makes a very thick copper bar out of the cable.

Can you send me the link from princess auto and how big of connectors you got?

PlayersZ28 · 02-22-2018, 03:29 PM

Quote:

Originally Posted by ibra0078

Can you send me the link from princess auto and how big of connectors you got?

Think I used 0-gauge for my battery connects. I just went into the store and they measured it off a roll.

Here's a link to all the different sizes. https://www.princessauto.com/en/sear...=welding+cable

These are the lugs I used https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

CampNow · 02-22-2018, 10:28 PM

Quote:

Originally Posted by PlayersZ28

I used welder cable from Princess Auto for my connections. I got lugs and shrink from Amazon. I used a very large Phillips screw driver and a steel V-block to crimp the lugs on. I did solder one cable but that just makes a very thick copper bar out of the cable.

A lot of folks, including myself, have crimped cables using "hammer" crimping tools. They do work, but the crimps are less than ideal---especially with very large 1/0 - 4/0 gauge cables. For our last project we purchased a 16-ton crimper (vs. the more common 10-ton) for $40 on Amazon (along with some bulk welding cable from temcoindustrial.com). Sounds like a lot of money to spend for one project, but for us we got our $40 and more back doing only 15-20 crimps. This hydraulic crimper, along with the use of moisture resistant adhesive shrink-wrap, produced cable lugs as good as any custom cable fabricator---at a fraction of the cost. You get professional low-resistant connections, reliably, quietly, quickly, with very little effort. Plus you end up with cables cut to the exact length needed, for every cable run, giving a very professional look.

For those that are very dollar conscience, I'm sure you could sell a 10-16 ton crimper on Craigslist in short order for $20-$30 after your project is finished.

Just some food for thought.

PlayersZ28 · 02-23-2018, 09:09 AM

Quote:

Originally Posted by CampNow

A lot of folks, including myself, have crimped cables using "hammer" crimping tools. They do work, but the crimps are less than ideal---especially with very large 1/0 - 4/0 gauge cables. For our last project we purchased a 16-ton crimper (vs. the more common 10-ton) for $40 on Amazon (along with some bulk welding cable from temcoindustrial.com). Sounds like a lot of money to spend for one project, but for us we got our $40 and more back doing only 15-20 crimps. This hydraulic crimper, along with the use of moisture resistant adhesive shrink-wrap, produced cable lugs as good as any custom cable fabricator---at a fraction of the cost. You get professional low-resistant connections, reliably, quietly, quickly, with very little effort. Plus you end up with cables cut to the exact length needed, for every cable run, giving a very professional look.

For those that are very dollar conscience, I'm sure you could sell a 10-16 ton crimper on Craigslist in short order for $20-$30 after your project is finished.

Just some food for thought.

I looked into getting one of the crimpers. Being in Canada it would have taken a while to get from the US (price in Can was out of line) so I skipped it. Next time I do an install though I'll get one. The way I did my crimps is similar to the hammer unit but I got them tighter. I used the adhesive lined heat shrink.

GrumpyDad · 02-23-2018, 12:22 PM

Quote:

Originally Posted by CampNow

A lot of folks, including myself, have crimped cables using "hammer" crimping tools. They do work, but the crimps are less than ideal---especially with very large 1/0 - 4/0 gauge cables. For our last project we purchased a 16-ton crimper (vs. the more common 10-ton) for $40 on Amazon (along with some bulk welding cable from temcoindustrial.com). Sounds like a lot of money to spend for one project, but for us we got our $40 and more back doing only 15-20 crimps. This hydraulic crimper, along with the use of moisture resistant adhesive shrink-wrap, produced cable lugs as good as any custom cable fabricator---at a fraction of the cost. You get professional low-resistant connections, reliably, quietly, quickly, with very little effort. Plus you end up with cables cut to the exact length needed, for every cable run, giving a very professional look.

For those that are very dollar conscience, I'm sure you could sell a 10-16 ton crimper on Craigslist in short order for $20-$30 after your project is finished.

Just some food for thought.

This really appeals to me. Although I haven't yet had a need to use such large cable. My little trailers don't draw so much amperage.

PlayersZ28 · 02-23-2018, 01:42 PM

This is the crimper I considered 2 yrs ago when I did all my wiring.

https://www.harborfreight.com/hydrau...ool-66150.html

curver900 · 02-23-2018, 02:42 PM

I just fired up a torch and soldered them on... all the connections in my boat.. heat shrink the connections... and good to go...

CampNow · 02-23-2018, 02:45 PM

Quote:

Originally Posted by PlayersZ28

This is the crimper I considered 2 yrs ago when I did all my wiring.

https://www.harborfreight.com/hydrau...ool-66150.html

This looks like a smaller, 8 ton crimper. It only crimps cables from up to 0 gauge (one review said it had trouble crimping a 0 gauge cable). Not to mention a little pricey at $55. Still pricey even at $44 with a HF 20% off coupon. It's unable to crimp larger gauge cables like 1/0, 2/0, 3/0, and 4/0---which are very common when installing higher-current RV converters and inverters.

If you're only going to be crimping smaller gauge cables I'd suggest purchasing a 10-ton crimper from Amazon or eBay for about $30-$35. Ideally, I'd suggest purchasing a 16-ton crimper. These will easily crimp cables from approx. 8 gauge to 4/0, and larger. There are a number of 16-ton crimpers are available on eBay for around $35-$40. For a few dollars more it offers a lot more functionality vs. a 10-ton crimper.

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