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HR-Sue-TN · 06-16-2014, 12:22 PM

Hi all, I just bought a 27' Aluma lite. Here's some info:

It has no generator but it's not a dealbreaker as I would like to eventually put in solar panels. The house batteries (2-12V, marine) were purchased 4 years ago.

When on shore power, all electronics work but once unplugged, the outlets don't work but lights still do. If it's a converter problem or if the master switch (salesman's switch?) has been turned off, shouldn't the lights stop working? I've looked for that switch by the entrance door but don't see one. Can low batteries supply enough to power the lights but not the outlets? I need to buy a multimeter and learn to use it as there are a couple of other issues but I'm hoping you have a quick answer for me. I've done a lot of reading the last couple of months (probably just enough to get myself in trouble). Thanks!

I did find a thread with a similar problem-I think he ended up switching relays and batteries, IIRC.

BFlinn181 · 06-16-2014, 01:23 PM

Your RV has two different electric systems. The 12 v system is powered by your batteries when unplugged, your Converter/charger when plugged into shore power. The Converter/charger not only charges the batteries but also provides power to lights, thermostat, refrigerator, water heater, etc. A battery disconnect switch usually disconnects most functions of 12 v house power, but not all, so leaving RV in storage could still discharge batteries.

The 120 v system is powered by the shore cord plugged into an appropriate outlet. When unplugged, the only way to get power to the outlets would be to an Inverter installed. They change 12 v direct current to 120 v alternating power. They deplete batteries quickly and aren't a replacement for a generator.

You may wish to read more here:

The 12volt Side of Life (Part 1)

In addition, add info about your RV in your signature line. When searching for a 1985 Alumi lite XL photos turn up of travel trailers, Class C, and Class A RV's.

HR-Sue-TN · 06-17-2014, 12:29 PM

Thanks, BFlynn.

From the linked article (thanks for posting that) it looks like the outlets are 110v, so it kind of makes sense that they would NOT work off of the batteries. But is there a way to make them work? I have two house batteries (12V, Marine deep cycle-I know I should replace them with a couple or four 6V ones) that appear ok-they are reading 12.68V. This makes me think my converter/charger is ok.

Wouldn't an inverter be installed by default so the outlets would work off of the batteries when not hooked up to shore power? Or are they assuming that most people would run a generator at that point? (Would the outlets work if I installed a little generator? I was hoping to not go that route, preferring to try solar instead.)

Sorry for all of the questions. If there's another thread/subforum that this would be more appropriate, please let me know. Thanks for your help.

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The rv is a class c and I think I'm the fourth owner. The roof was sealed a long time ago with some tape (Eternabond?) and is in amazing shape. From the decals on the unit, it looks like it belonged to quite a few clubs and attended many rallies. I wonder why the original owner sold it. The rv probably has lots of interesting stories to tell.

BFlinn181 · 06-17-2014, 12:49 PM

The problem with inverters is they can drain a couple of batteries, even deep cycle ones, pretty fast. They also are expensive and not regular equipment of an RV of your vintage. Inverters also can be Pure Sine Wave or Modified Sine Wave type. The MSW is usually cheaper, but doesn't play well with some things that run on 120 v AC power.

http://www.xantrex.com/documents/Tec...-Universal.pdf

An inverter large enough to run a coffee maker, hair dryer, or microwave would cost $150 or more. The length of time you could consume power at those rates is short and the charge cycle would require lots of time.

Inverters are inefficient, the best are close to 90%, many are 80% efficient, so you lose a lot of capacity in the device itself.

Forest Grump · 06-21-2014, 08:04 PM

I have a 3000 watt inverter in my MH and love it. I have 3 12v J-125H Trojan 215 Ah batteries for a total of 645 Ah. We run the microwave, TV, Bluray, hair drier and vacuum off it. It is modified sine wave and everything runs very well. We run the generator to charge the batteries every 3 to 5 days.

If you use high quality deep cycle batteries with a hight quality inverter with very conservative 12v wire gauges you will have a good setup. Skimp and you will be disappointed. Batteries are 5 years old.

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