Question about wiring my brake controller.

[twobighemis]

I bought a tekonsha primus, and im installing it in a dodge ram that did not have the factory tow pkg.  

I only have one concern:  What gauge wire should I run back for the 12v+ ?

[wavery]

My wiring warness instructions recommended 14g. Remember that bigger is better. When running long distances you will experience some voltage loss with smaller cables.

This wire will be charging your camper battery and possibly be running your 12v fridge (if you have one). It's best to get the biggest bang for your buck while charging. I used 12g on mine. 10g may be a bit of over-kill.

Just a note....I used tinned marine wire, soldered all splices and used shrink wrap. It's a little more expensive but sure cuts down on corrosion problems and the tinned wire is a breeze to solder. The shrink wrap keeps out any moisture.

[SpeakEasy]

My wiring warness instructions recommended 14g. Remember that bigger is better. When running long distances you will experience some voltage loss with smaller cables.

This wire will be charging your camper battery and possibly be running your 12v fridge (if you have one). It's best to get the biggest bang for your buck while charging. I used 12g on mine. 10g may be a bit of over-kill.

Just a note....I used tinned marine wire, soldered all splices and used shrink wrap. It's a little more expensive but sure cuts down on corrosion problems and the tinned wire is a breeze to solder. The shrink wrap keeps out any moisture.

You can take the sailor out of the sea, but you can't take the sea out of the sailor, right Wavery?

[AustinBoston]

My wiring warness instructions recommended 14g. Remember that bigger is better. When running long distances you will experience some voltage loss with smaller cables.

This wire will be charging your camper battery and possibly be running your 12v fridge (if you have one). It's best to get the biggest bang for your buck while charging. I used 12g on mine. 10g may be a bit of over-kill.

Just a note....I used tinned marine wire, soldered all splices and used shrink wrap. It's a little more expensive but sure cuts down on corrosion problems and the tinned wire is a breeze to solder. The shrink wrap keeps out any moisture.

If the +12V is the +12V output of the electric brake controller, then 14 gauge is OK.  Brake wires should be blue if possible.  But if he's talking +12V Aux, then it needs to be at least 12 gauge, and 10 gauge would be better.  Most are fused at 25-30 amps, which would melt a 14 gauge wire.

Austin

[wavery]

You can take the sailor out of the sea, but you can't take the sea out of the sailor, right Wavery?

I was thinking the same thing. However, years ago, when I built my dune buggy trailer (and later a toy hauler), I remember having problems with trailer wiring. It was usually due to corrosion from using crimp connectors. I learned how to do it right when I had the boat. EVERYTHING had to be soldered and shrink wrapped. I did that on this trailer wiring, just to avoid problems.

They also make crimp connectors with shrink wrap already build in (again, marine store stuff). Those are really neat because you crimp it, then heat the connector. That activates the shrink wrap and also seals the connection with a low temp solder.

[twobighemis]

I'll go for 10 gauge then since it will be for aux power.  Thanks

[CAPEd CODger]

Just to add a little "fuel to the fire", I thought I'd throw in a little tidbit of information.
I found a chart with the load ratings for wire here: http://www.powerstream.com/Wire_Size.htm

I've been installing and servicing two way radios for the last 30 years, and for a radio with a 40 amp fuse, the manufacturer puts an 8 gauge wire on the cable that goes from the battery to the transceiver in the trunk of the car.
The average current draw during transmit is around 20-25 amps.
No doubt, the bigger the wire, the less voltage drop will occur under load.

Happy Camping

[twobighemis]

Why does the factory harness only have 16-18  gauge run back to the bumper on a vehicle equiped with the 7 way plug?

In fact, Im pretty sure there isnt a factory breaker switch for it either.  Should I install a breaker?

[wavery]

Why does the factory harness only have 16-18  gauge run back to the bumper on a vehicle equiped with the 7 way plug?

In fact, I'm pretty sure there isn't a factory breaker switch for it either.  Should I install a breaker?

If it's a factory harness, you can be sure that it is fused. Probably a 20 amp fuse in your fuse panel. Check your owner's manual. It should be listed. It may just say "Aux" or it could be run thru your "Accessory" fuse (but I doubt it). You could check it by putting a test light on the power lug then pull fuses until you hit the one that turns the test light off.

[twobighemis]

Thanks for all the help guys!

[AustinBoston]

If it's a factory harness, you can be sure that it is fused. Probably a 20 amp fuse in your fuse panel. Check your owner's manual. It should be listed. It may just say "Aux" or it could be run thru your "Accessory" fuse (but I doubt it). You could check it by putting a test light on the power lug then pull fuses until you hit the one that turns the test light off.

It might hace a self-resetting breaker.  BTW, this is a situation where the line really needs two fuses, one at each power source.  If the TV fuse blows, the trailer battery is more than capable of providing enough current into a short to melt the wire or start a fire, so it should also have a fuse or breaker.

Austin

[twobighemis]

It might hace a self-resetting breaker.  BTW, this is a situation where the line really needs two fuses, one at each power source.  If the TV fuse blows, the trailer battery is more than capable of providing enough current into a short to melt the wire or start a fire, so it should also have a fuse or breaker.

Austin

Yeah, ive got a fuse at the trailer battery, i'll  make sure to put one under the hood too.