Powered Electrical Outlet in AS While Moving???

[Mark of SJC]

Hi!

I'm sure this is a newbie question, but we're trying to figure out if this will work. We are bringing a small second refrigerator/freezer that runs off both a cigarette lighter and regular plug in - but it won't fit in our truck.

We are hoping that there is a "live" electrical outlet in the AS that we can plug into for 2 ~3 hours - only while we are underway. The truck has a huge alternator and I know a small amount of electricity can travel from truck to trailer...but I would assume that I need to have the inverter on during this time (batteries are fully charged).

Assuming there is no way to power this through a DC connection (is there?), would I be okay in this scenario running the inverter? And are only some plugs powered by the inverter, or all all of them?

Our destination has full 50 amp service.

Any help would be appreciated!!!

[Wrangler]

Your trailer should have an inverter that provides 1500 watts of 110 V AC. My FC has an inverter supplied outlet under the dinette. This may be enough power to run your small refrigerator.

[overlander63]

The inverter is probably 1000 watt. It will need to be physically turned on, with the indicator light glowing green on the switch panel, and will only power the outlets labeled for the inverter.

[kidjedi]

If the portable fridge runs on both AC and DC, why wouldn't you use a 12v connection in the trailer so you're running the fridge directly off the house batteries and (and your alternator) while driving? If you use the inverter to power it with AC 120v, you're using the same source, just wasting power on the conversion.

[batman]

^^^ Ditto^^^Kidjedi. Just use a 12V cigarette lighter connection inside the trailer!!! Inverters are horribly inefficient and will suck the life from batteries in a hurry.

-Dennis

[uncle_bob]

Hi

How much does the "small fridge" pull on 12V? 5A ... 10A .... 20A ... it could be anything in that range. Best to check this first.

*IF* it pulls 20A, your batteries are good into the ~80AH range when fully charged. You would get your ~3 hours run time, but arrive with near flat batteries running off 12V. If you toss the 5A or so of "overhead" from the inverter on top of that, you are getting pretty close. This of course *assumes* your batteries are indeed fully charged and that they still deliver full rated capacity.

The wires that run from the front of your truck way way back into the trailer are only just so large. The truck alternator drops back once the battery in the truck is topped off. Otherwise it will boil your truck battery. The net result is that if you get 5A though that wire you are doing pretty well. It's not going to be a big help *if* the fridge is in the 20A range.

Best bet, no matter what the rating is: Fill it up the night before. Let it run on shore power (like in the garage). Get it good and cold *before* you put it in the trailer. That will minimize the current draw, regardless of what the max numbers are.

Indeed the fridge *probably* doesn't pull full rated power all the time. There are some that do ....

Bob

[coasttocoast]

I use a Goal Zero 3000. You might look at a 1500 also if you just need power for a few hours. REI currently has 20% off for members.

[TrailDude]

Originally Posted by kidjedi

If the portable fridge runs on both AC and DC, why wouldn't you use a 12v connection in the trailer so you're running the fridge directly off the house batteries and (and your alternator) while driving? If you use the inverter to power it with AC 120v, you're using the same source, just wasting power on the conversion.

Newer Airstreams do not come with a 12 volt cig lighter plug, only USB. If this is something you plan to do regularly it would be more efficient to install a 12volt receptacle. While I am no electrician I have read the simplest way is to convert one of your USB ports.

[Wazbro]

Originally Posted by TrailDude

Newer Airstreams do not come with a 12 volt cig lighter plug, only USB. If this is something you plan to do regularly it would be more efficient to install a 12volt receptacle. While I am no electrician I have read the simplest way is to convert one of your USB ports.

Please realize USB ports are 5V "IF" they are supplied by 12V (should be in trailer) you would need to tap into the power supply line or replace the port with lighter outlet or lighter outlet with USB ports or tap into power for a 12V light.

Also note requirement to check amp draw most 12V circuits in ASs (at least were) 20 amp, this really means 15 amps continuous.

[rucos]

I tried using my slow cooker thru the inverter a year ago while on the road .... I left the house with the cooker already working ...put it in the sink to be safe and plugged into the inverter. When we arrived 4-5 hrs later the stew was ready.... no great battery drain but it was only maintaining temp as I preheated at home. I also was going to a full service site so I wasn't worried about running my batteries to low.
It was nice walking into the trailer smelling of dinner on arrival....... ive only done it once but it worked fine.

[BayouBiker]

If this is infrequent it may not be worth the hassle of rigging up 12v power. The inverter draws 2A itself and the refrig unit between7 and 10. The vehicle will charge back 3-10 Amps so if your batteries are charged or nearly so, the inverter is an inefficient but easy option

[Photobum]

I do something similar but I use a Yeti 75.

[cbburke]

Last year we spent 4 months on the road with a BiMart special 3 cubic ft freezer. We carried it in the back of our truck and kept it plugged in when ever we stopped for the day. The freezer was good enough to maintain the contents frozen the entire trip. The result was the same as the built in refer/freezer. Both appliances maintained their temperatures for 4 plus hours of travel during the summer.

[Overstreet]

My California friends drive up to Alaska on normal years in July. They have replaced the dinette table with a small chest freezer. They fish for salmon and fill up the freezer. Once frozen they drive back home stopping each night to plug in and "recharge" the coldness of the freezer.

Every year or so here, in Florida, there is a big storm that looses our power. Freezer is off for up to 12 hours but usually 6-8. Once storm over we plug in the generators outside.

In those two cases the frozen stuff stays frozen. Maybe you don't have to worry about continuous power.

[gcarter]

Those small freezers use a 12V compressor. So if you use the inverter you convert 12v to 110v and then 110v to 12v. Your actual wattage will be less using 12v into the freezer.

[TouringDan]

I have experience with two different compressor fridges. Both of them draw about 50 watts and run about half the time. The compressors are 12v so it is best to just operate them using a 12v outlet in yourAirstream. If you don’t have a 12v outlet, then I would install one (or several).


Here is a photo of the 35 qt compressor fridge that I carry in my car. We also carry a 65 qt compressor fridge in the bed of our Tundra- the TV for our Airstream.

Dan