'School me' on the basics - Electric 101.

[NJtoNC]

jim,

I've seen the prices on those 2000 /3000's and my bank card shuttered
I'm trying to avoid the generators b/c i have a feeling i won't re-coup the $$ we spend on it.

still researching on the batteries. 1000 watt batteries sound hardcore!

new axle is researched and ready to order.

amazingly, when we got the trailer it was in near perfect condition. still has bright blue paint on the emblems, warranty label inside closet, and even the wiring looks brand new. this girl must've been in a garage for 50 yrs. only issues were mousies and water tank batteries removed. frame looks solid, not even a bit of water damage to floor. I know, i still have feelings like i should've traded it for a worse condition trailer to reno so this great example would have been preserved.

but trailers were meant to enjoy, not to sit forever untouched. so we reno'ed.

[arodriguez60]

If you use an inverter you need a true sinewave inverter. ac motor do not do well with modified wave inverters

[Jammer]

You can't run the air conditioning from batteries. It just won't work, too much power. You can't run it in cool mode or in heat pump mode.

For battery sizing you figure in terms of amp hours at 12 volts. The amps required will be about ten times the amps at 120 volts, so take that and multiply by how many hours your going to run stuff.

Two GC-2 batteries should give you around 100 amp hours at a reasonable depth of discharge, at 12 volts. That means for a 24 hour stay your average amp draw has to be below 4 amps. Things like the fridge matter most. Water pump matters little because it doesn't run much. Lights, somewhere in between.

If you use an inverter to power stuff, you have to figure that the best inverters available draw about 11 amps from the 12 volt battery for each amp of 120 volt power they produce. Cheap inverters draw more. It's easy to see why running electric heat or air conditioning won't work this way.

[NJtoNC]

im sorry im a bit slow at this...

The amps required will be about ten times the amps at 120 volts, so take that and multiply by how many hours your going to run stuff.

is there a formula? 10 x 120V x 24 hours?

sorry for the lack of comprehension...
: /

[arodriguez60]

the formula is volt x amps = watts
if you run a microwave which is 1000 watts at 120 volts you would need 8.3 amps on 12 volt you need 83.3 amps to run it not including the power that the inverter uses.

[TG Twinkie]

I want to read all of these post so I just stuck this note here so I can find it later. Is there another way to do this?

[Jammer]

Let's take the fridge as an example. 1.5 amps at 120 volts.

If you run it on an inverter, it will use approximately 10 times as many amps, so that's 15 amps.

Fridges typically run about half the time, because the thermostat turns them on and off. So, in one day (24 hours), the fridge will run about 12 hours. 15 amps * 12 hours = 180 amp-hours. That makes for a big battery bank, which is why I'm suggesting that you do something different.

If we looked at the air conditioning, it draws 8 amps at 120 volts. If you ran it through an inverter, it would draw around 80 amps and 12 volts. If you decided to run it for six hours on a hot afternoon, you'd need 80 * 6 = 480 amp-hours of battery capacity just for that, which would completely discharge four brand new deep cycle batteries of the sizes typically used in Airstreams.

[fotochop]

Originally Posted by TG Twinkie

I want to read all of these post so I just stuck this note here so I can find it later. Is there another way to do this?

"Thread Tools" menu item, scroll down and
"Subscribe To This Thread" (or 'add sub' whatever it says etc)

[NJtoNC]

Originally Posted by Jammer

Let's take the fridge as an example. 1.5 amps at 120 volts.

If you run it on an inverter, it will use approximately 10 times as many amps, so that's 15 amps.

Fridges typically run about half the time, because the thermostat turns them on and off. So, in one day (24 hours), the fridge will run about 12 hours. 15 amps * 12 hours = 180 amp-hours. That makes for a big battery bank, which is why I'm suggesting that you do something different.

If we looked at the air conditioning, it draws 8 amps at 120 volts. If you ran it through an inverter, it would draw around 80 amps and 12 volts. If you decided to run it for six hours on a hot afternoon, you'd need 80 * 6 = 480 amp-hours of battery capacity just for that, which would completely discharge four brand new deep cycle batteries of the sizes typically used in Airstreams.

ok, that math makes sense!!! thank you.

we'd essentially need 2 batts for just the fridge for 1 day.

Instead of purchasing an expensive LP or 12v fridge, right now i think ill stick with my cheapo compact 115v fridge, and instead of running the fridge on dry camping days, We'll get ice for the cooler. SOLVED.

I'm not sure that kind of purchase (12v or LP fridge) would pay for itself anytime soon. perhaps if we find ourselves boondocking more often in the coming years we will upgrade.

[WILDRTEXAS]

Whew, LOTS of solid info here. Dont understand it, but I like it.
Im in awe of all you that do Thanks for the lessons.

[fotochop]

"Instead of purchasing an expensive LP or 12v fridge, right now i think ill stick with my cheapo compact 115v fridge, and instead of running the fridge on dry camping days, We'll get ice for the cooler. SOLVED. "

NOW you're thinking like a 'streamer! and less is usually more... but as one who really LOVES his propane fridge (like all the duck hunters out in the marsh with camps that have them..) keep it in mind maybe for a long-term purchase, especially if you already have the venting....

[JimGolden]

True enough, you could get buy for awhile by just sticking a bag of ice in the old fridge. A decent LP fridge will last you twenty years, so they are an investment.

I bought a new Dometic fridge through Palomino Parts last year, and it's a dandy. Way better than my old one...but the old one lasted 22 years before she gave up the ghost. So, you could get by with whatever you must for awhile, but I think you'd really like a good LP fridge.

It sure sounds like you found a really superb trailer. What a cool project!

see ya on the road,

[fotochop]

re: propane fridges believe it or not, there's this incredibly nice guy in Alabama who repairs RV propane refers:

Rv Refrigeration Repair

..and I think he'll overhaul just the cooling unit (if you can remove and ship it to him) and make your old dometic good as new!

...I just get such a kick out of seeing that tiny blue flame making ice cubes...I dunno..I can't explain it...fire into ice...ain't science wonderful?

...and when traveling, we use those blue jelly freeze fake-ice things to keep the fridge cold, no melted ice water to deal with..... we now return you to our regularly scheduled thread...

[lightng]

I'm going back to school on a shoe string and living full time in my 25 ft. Excella-2001. I plugged my 30 amp (with an adapter) to a heavy dury extention cord to the interior house outlet. I use very little electric. A light, lap top computer, fridge, sometimes a fan. I tried using my hair dryer once. The extention cord has some kind of fuse on it and it would not tolerate the hair dryer.So, I don't use it. Today ,while using minimal power, the cord turned itself off. I checked the AS 30 amp cord and adapter- it was hot and damaged. Checked the house socket and the brain surgeon that is doing repairs in the house had a barn buster heater plugged into the same socket.
I know I need to replace my damaged AS 30 amp cord-- if nothing else was plugged into a house outlet--can I safely use this power source to run the fridge, a light, and computer? thanks for any help

[richinny]

a few facts are needed.
breaker rating on the house outlet (and gauge of wire if known)
gauge of extension cord and length
any power draw info on the items you are using. btw, the converter uses power too.