few questions about electrical re-wiring in a camper

[Apache82]

Hey everyone! Glad to be a part of this forum.

I am renovating a 1979 15' travel trailer for myself.

Previous owners pretty much cut everything out. plumbing, water tank, toilet, shower and a lot of the electrical.

I have installed a water tank and water pump, but mainly have questions about how all the electrical works in these things.

from the breaker panel (30amp) they ran 12-2 wire to the outlets, which I then used the hots to run to switches for lights. Can I just run this 12-2 wire to a regular light switch or something and then to the pump? or do I need to use a special pump switch? I don't really see the difference...

Also, all these red, blue, yellow, wires, etc... are they ONLY for the exterior lights? (tail lights, etc..) ???

They have basically two breakers for every thing inside. I am attempting to have the lights and outlets on one.. and the electrical heater, water pump and a little window ac unit on the other... too much or ok?

THANK YOU!!!

[Lwiddis]

All TTs are wired the same. It’s basic. A 12 volt system for some things that uses the battery/ies or is fed by the converter if plugged in, and a 120 volt system that runs items like the A/C and microwave and feeds the 12 volt system when plugged in. Before you wire anything do extensive reading.

[DrewE]

It sounds as though this did not have a 12V system, or much of one, to start with; the loose wires for tail lights etc. would be 12V wiring, and powered from the tow vehicle and completely separate from the 120V system. Assuming you have electric brakes on the trailer, it would be wise to install at least a small 12V battery and switch etc. for a breakaway braking system (that would apply them should the trailer somehow become detached from the tow vehicle). Many states require such a system, at least for larger/heavier trailers.

It probably is obvious, but if the water pump is a 12V pump, don't connect it directly to a 120V circuit if you want it to continue to work. Virtually all RV water pumps available today are 12V DC devices.

I would suggest at least thinking about putting in something of a 12V system with a couple of interior lights etc. and replacing the electrical distribution panel, assuming it's just two AC fuses or circuit breakers and nothing more, with a small RV panel that has AC breakers, DC fuses, and a converter (to power the 12V system and charge the 12V battery when hooked up to 120V shore power). This PD4045 is one example of a good unit to consider. It would give you space to have more AC circuits (which, while I don't think absolutely necessary, would be better.)

Do make sure you keep the ground and neutral busses separate in the RV. They are not bonded together at the RV panel, unlike a house main panel. The entire RV acts as a sort of sub-panel to the campground or whatever it's plugged into.

[time2roll]

Verify the equipment and fixtures are rated 120vac before you pull wire and connect. Most RV lights, pump, fans etc run on 12 volt battery power.

Use regular stranded primary wire for 12v systems... not romex to avoid confusion.

[Farmboy666]

Are you doing a 120v and a 12v system or just 120v? Answer that and you will geet the answers you need.

[ScottG]

Yes, you can do as you describe. It will be perfectly functional.

To know what the other wires do, you'd need to ring them out.

[punomatic]

Apache82 wrote:
Hey everyone! Glad to be a part of this forum.

I am renovating a 1979 15' travel trailer for myself.

Previous owners pretty much cut everything out. plumbing, water tank, toilet, shower and a lot of the electrical.

I have installed a water tank and water pump, but mainly have questions about how all the electrical works in these things.

from the breaker panel (30amp) they ran 12-2 wire to the outlets, which I then used the hots to run to switches for lights. Can I just run this 12-2 wire to a regular light switch or something and then to the pump? or do I need to use a special pump switch? I don't really see the difference...

Also, all these red, blue, yellow, wires, etc... are they ONLY for the exterior lights? (tail lights, etc..) ???

They have basically two breakers for every thing inside. I am attempting to have the lights and outlets on one.. and the electrical heater, water pump and a little window ac unit on the other... too much or ok?

THANK YOU!!!

It sounds like you are wiring everything for 120V AC. That's OK if you expect to be plugged in to shore power all the time. Most travel trailers have a 120V AC system that powers AC, some outlets, maybe a water heater element, maybe a fridge and a power converter.

Then there is a 12V DC system that usually powers lights, water pump and the circuit boards for things like propane water heater, propane side of fridge, propane heater.

The interface between the systems is via the converter, which when connected to shore power, supplies 12V DC to all the DC appliances and charges a 12V DC battery bank.

If you don't care to be self contained (i.e., able to operate appliances when off the grid), you can use all 120V AC appliances and wire accordingly. Typically, an RV water pump will be 12V DC, so you would need to find another kind of pump. OTOH, if you are connected to shore power, you can also probably connect to city water and delete the water pump altogether.

Here is a great treatise on RV electrical systems: The 12 Volt Side of Life

[jim1632]

From your user name, you may be working on an Apache. If so these are very popular and you should just search for Apache remodels on the forum.

Otherwise use your trailer brand here and in YouTube for info.

I now use YouTube for all may problems. If solution is simple, I avoid the dealer. If more difficult, I can learn enough to avoid dealer double-talk.