Electrical System Set-Ups

[WhittleBurner]

This is a great discussion. We are hooking up a 100 watt solar panel this spring and already have 2 6v batteries. We had solar on a previous trailer, but it was much
simpler then and our usage was very minimal. I'll be reading and hopefully learning more of how to do what we want to. We'll keep it portable until we decide otherwise. Hooking up an inverter is something I'd like to do.

looking forward to more and posts of how tos!

[Soldotnatom]

This thread provides excellent information. In considering installing an inverter in my 303rls I have discovered wiring layouts that can create some real problems. One use of an inverter is to power the television. Oddly, IMHO, the Ac circuit for the television is on the same circuit as the refrigerator for 110V. Makes it difficult to just conbect that circuit to an inverter. Iff you forget to force the frid to propane your batteries will be toast very quickly. Given how the wires are run it would be difficult to put the television outlts on a separate branch circuit.
The electrical wiring layout could use improvement in the 303. Another example are the ceiling light switch being on the panel with slide switches behind a door. Also, labeling two diiferent breakers as 110 receptacles. Which ones on which?

[scott42blue]

Hi Randy,

"Equalizing" cells at 14.5 V to reach 100% is a technology of very sophisticated battery chargers.
But, you are absolutely correct.

I also used to solder terminals until I discovered the lug crimpers used to attach welding cable lugs.
The problem with soldering (at least in the marine environment) is that the flux keeps corroding things.
Shrink wrapping is a way to seal in the flux acid . . . but is not required with crimped connections.

Good discussion !!

Rob

Another problem with solder and reason no manufacturers use it. In the event of a serious short with a large cable it is possible to melt the solder free one or more cables and make a bad situation much worse.
Scott

[james quinn]

I'm gonna throw a question out there.

I am considering relocating my battery to the rear of my 313rlts TT to help take weight off the tongue. If I was to put two 27 size batteries back there (37 feet from OE location) what size wire(s) would I need. From where I am sitting in Starbucks, I can see a hydro tower and I'm thinking that maybe I'll climb up and hack off a chunk

[Cate&Rob]

Hi Jim,

See post #5 on this thread . . . I wondered a long time ago, why GD doesn't put the batteries aft of the axles ! Would benefit everybody except maybe the toy haulers.

One of the electrical guys can probably quote you cable size for that distance. Or I can look it up per ABYC standards. For reference, I used 1/0 ga fine stranded wire for a similar distance run from my battery bank to the anchor windlass on my boat. The windless draws 80 amps with minimal voltage drop. You have to consider both directions for resistance loss (70 ft of wire) unless you are going to use the trailer frame as ground . . . which might be OK. I don't think you would need to provide for this kind of amperage unless you are running two slides at once . . . or something similar.

If you decide to do this, the most affordable high quality heavy gauge wire is from a welding supply store.

Rob

[J&G garage]

It depends on the max current you think you will need. If you use decent tinned, fine strand wire it would cost you about $350 for your 75 foot run (from batteries out and back) for 2 gauge wire to carry 20 amps. 50 amps would run you almost $600 for 2/0 wire. Add in the cost of fuses, fuse holders, terminals, insulating covers for the fuses and battery boxes and there goes your Starbucks. When I installed a windlass on my boat the cost of the wire, terminals and fuses was over a $1000 for a similar length run. If I remember the windlass didn't cost much more than the wire.

Jim

[james quinn]

It depends on the max current you think you will need. If you use decent tinned, fine strand wire it would cost you about $350 for your 75 foot run (from batteries out and back) for 2 gauge wire to carry 20 amps. 50 amps would run you almost $600 for 2/0 wire. Add in the cost of fuses, fuse holders, terminals, insulating covers for the fuses and battery boxes and there goes your Starbucks. When I installed a windlass on my boat the cost of the wire, terminals and fuses was over a $1000 for a similar length run. If I remember the windlass didn't cost much more than the wire.

Jim

uhhh, so, throw the batteries in the back of my truck and strap a 9 volt to the trailer for the drive ? So much for THAT idea !!!

[james quinn]

[quote= and there goes your starbucks.

jim[/quote]

nooooooooooooooooooooooo !!!!!

[james quinn]

I'm a little bit confused ... trust me, it ain't the first time.

Household wiring: #3 wire is good for 100A service. Now I admit to not knowing tons about 12V but if #3 is good for 100A with 120V I don't understand why it wouldn't work in my case. The link below is pretty cool and when I enter numbers in the calculator it shows a next to nothing voltage drop at 80A draw. Me so confused

http://www.powerstream.com/Wire_Size.htm

[J&G garage]

Household wiring isn't designed for 12 vdc vehicle use (whether or not RV manufacturers use it for such). If you're going to the trouble of rewiring a portion of your RV, IMO you might as well do it right with wire and terminals that are designed to handle the vibration and stay in use for years without corrosion issues. In addition gauges of wire I referenced are required for current and DC voltage I mentioned in my response above for a 3% voltage drop. This is the chart I found quickly on the internet:

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

The chart I used assumed 12vdc. You actually are working between 12.7 vdc and 12.2 vdc in your coach not 12 vdc.

If I use your chart at 12.7 vdc I get 1 AWG at 3% voltage drop for 20 amps. Now you don't even get Folgers coffee.

Jim