Help with 12 Volt interior lights

[pcasa]

Just got my 66 Caravel back from having some work done - all electric was working fine previously and during its stay at the "hospital". But now when I plug into shore power - (I no longer have batteries or use univolt) - the 12 volt lights are not working. My outlet plugs are all working fine.

I've tried new bulbs - but repairman thinks there must be a blown fuse. I have checked the 1966 manual and I see a diagram for 4 fuses but I cannot locate where they are in the service area.

can anyone help me troubleshoot???

Thanks!

paula

[A W Warn]

If you no longer have batteries or univolt, where does the 12v DC for the lights come from?

[overlander63]

Without 12v, your 12v system will not function. Since you have removed any source of 12v, nothing will work.

[pcasa]

I've owned the trailer for 10 years - no batteries - just shore power and everything has always worked fine. And the old univolt is still there, I just assumed it wasn't functioning all these years since there were no batteries.

[pcasa]

Just double checked the toggles - I reset them to city power and now lights are working.
Thanks for helping me uncover the obvious!

[drhuffman]

I know this is an ancient post, but can anyone tell me where these toggles are that need to be reset? Thanks!

[pcasa]

Hi, if you have referring to the Power toggles - they are inside the utility compartment - street side - where your power cable is stored - look to left and you'll see the toggles mounted on a panel

[pcasa]

OK - CRAZY update question - apparently my 12V lights were running off the 110 power supply - and yes, they were super duper bright and bulbs burned out frequently - but I was too dumb to figure it out. So recently when I had a bunch of work done on my Caravel - a new breaker box was added and now the 12V lights no longer work on shore power. I was told to add a "24 battery" and they would work again. He has shown me the wires with connectors, but I would like to better understand what I am doing. Tips? Comments? Suggestions? and yes, I realize this is a bone-head question. thanks y'all! Paula

[A W Warn]

how 12 volt works in our trailers>

- Univolt is a brand name for a converter. People sometimes use the generic word "univolt" when they really mean "converter".

- 12 volt in our trailers comes from two places, the converter and the battery. (or from solar energy on those trailers that have panels)

- the converter is plugged into and changes 120volt alternating current to approximately 12 volt direct current. The current coming from the converter actually varies from about 12 volts and more than 13 volts, depending on need.

- when plugged into shore power the converter charges the battery and provides power to lights at the same time, or to either one individually. So if there is no battery present, you can say that the lights are running on 120v. But, in reality, they are running on 12v from the converter.

- the converter should provide current power the lights, even if there is no battery

ps:
The 24 series battery is minimum. If you boondock there are larger more capable batteries if there is space for it.
ps2:
If the light bulbs are extra brighter than normal and burning out often, the converter may be providing too much power. Is your converter still the old Univolt, or has it been changed to a more modern converter?

[lakemaiden]

Alan, thank you for this mini-tutorial. I would be curious to know what batteries you recommend for a boondock [and sorry pcasa, for taking this slightly off topic, but I've been wanting to know.] Thanks!

[DGJackson]

I highly recommend either of the following books. Both are available from the usual sources, I got my copy through Vintage Trailer Supply:

• RV Electrical Systems

• Managing 12 Volts

I constantly refer to both sources for system explanations or guidance.

Dennis

[Al and Missy]

Originally Posted by pcasa

OK - CRAZY update question - apparently my 12V lights were running off the 110 power supply - and yes, they were super duper bright and bulbs burned out frequently - but I was too dumb to figure it out. So recently when I had a bunch of work done on my Caravel - a new breaker box was added and now the 12V lights no longer work on shore power. I was told to add a "24 battery" and they would work again. He has shown me the wires with connectors, but I would like to better understand what I am doing. Tips? Comments? Suggestions? and yes, I realize this is a bone-head question. thanks y'all! Paula

If the converter in your trailer is original it is likely that it needed a battery to regulate the voltage. That could be why your lights were too bright and burning out. Changing the breaker box should not have affected your lights. If you don’t have a battery, and the cables are loose, the positive one may have shorted to the body of the trailer or the negative cable and blown a fuse or tripped a breaker. I think the older trailers had fuses.

First, decide what kind of battery you want. If you are always going to have 120 volt power, a single group 24 deep discharge rv battery should be fine. Get one and have it installed.

Next, find and check your converter to see what it is. It is a metal box somewhat smaller than a shoe box. If it is branded Univolt, or Parallax and looks old, replace it. I like Progressive Dynamics brand.

If your lights still don’t work it is probably a blown fuse you will have to find and replace.

Get help if you are not comfortable doing this.

Al

[A W Warn]

Originally Posted by lakemaiden

Alan, thank you for this mini-tutorial. I would be curious to know what batteries you recommend for a boondock [and sorry pcasa, for taking this slightly off topic, but I've been wanting to know.] Thanks!

I do not have a specific battery recommendation. There are so many battery choices, and people have different expectations, and people use their trailers at different time intervals (examples: daily or a couple times per year), there is no one size or battery type that fits all.

My recommendation for occasional boondocking is:
a. use the largest battery that will fit into the battery space provided without modifying the trailer.
b. charge the battery daily, either using a generator or solar. Charging can be on the less expensive end of the range (small generator/portable solar) or very expensive (solar array with multiple batteries). That is a choice each of us has to make.
c. If winter boondocking and using the furnace to heat, maybe add a second battery if there is only one in the trailer. Make sure the battery (or batteries) does not discharge more than it should.

Generally.... my preference, base on my frequency of use and cost, is deep cycle/marine lead acid batteries. This type of battery usually lasts 3 or 4 years and cost about $120, so ~$30 to $40 per year. I think mine is a group 33 (can't remember). Last time I purchased a battery made by East Penn Manufacturing, a US battery maker that has a factory near my home. They sell batteries under a variety of brand names. DEKA is one of their brands. I know that O'Reilly's Auto Parts sells the exact same battery under a different brand name. I spoke with an engineer from East Penn, questioning about the quality of the different brands they make. He assured me the battery of the same type/size of each brand is exactly the same inside. The only difference is the plastic box the battery is built in, which has the retailer's brand name.

In my Safari I changed to a large battery with more amp hours since my single battery box is large enough to accept it. When boondocking I charge every day, sometimes twice morning and evening in winter, with a generator. I don't boondock often (2 or 3 weekends per year) enough to justify the expense of solar and a battery bank.

[uncle_bob]

Hi

Backing up a bit .....

If you tow your trailer on the highway, it needs to have a breakaway setup on it. That system is powered by the battery on the trailer. No battery = no breakaway system. Since this is a legal requirement, there's not a lot of ways to get around it. ( = it voids your insurance ...) Indeed we've had to take trailers off the road when they no longer complied with similar rules about brakes.

Bob