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rdm 06-30-2003 11:43 AM

Fridge replacement/ Inverter needs
We have decided to replace our expired dometic fridge with a apartment sized unit from LG Appliance. This unit will run ac when plugged in or with the gennie running. We want to add an inverter to power the fridge while driving during the day.

How large a inverter can we put in without having to increase the coach batteries in size and number.

Also can you suggest a good make of inverter.

The fridge is rated 115V 60hz 1.5 Amp


Andre Baillargeon 08-28-2003 05:26 PM

There is a site call they have inverter and battery eliminator and if you get to the site look at the battery tutorial great reading. Andre

Pick 08-28-2003 08:03 PM

RDM, look at the power specs for the fridge. You will find "LRA" or Locked Rotor Amperes rating. This also equates to the starting current. My fridge is rated at 1.9 amps and LRA of 9 amps. A 400 watt/ 800 watt Vector will NOT start the compressor. At 1.9 amps, I think a 95AH battery will SAFELY run it 2 hours.

Fun-Lovin 08-28-2003 08:46 PM

I did some checking on this myself and contacted the manufacture of the Fridge Im currently looking to purchase. It shows a .95 amp draw on the back of the unit but they told me it requires 1.4 amps continuious and 4.6 amps to start the compressor. I asked them about using an inverter and was told that it requires 1400 watts minimum. I would recomment going to one of the boating suppliers for a good high current interter.

Best of luck,

RonJudi 01-20-2004 06:04 PM

I guess it is the electrical engineer in me that makes me want to reply. First, the inverter has many useful purposes but running a compressor is not one of them. A Compressor has a starting load and depends on a exact sine wave uniform operating signal. Though,inverters are getting better at this, the first bunch were really were only square wave generators. They are not suitable for running motors and will quickly burn them up. Getting a high current sine wave inverter that will run a compressor is very expensive and not very practical. The next problem is finding a battery which can supply the current needed to run a fridge and the inverter. If you need 5 Amps continuious at 120VAC then that means you need about 50 amps continuious at 14VDC. You can imagine how long your battery will carry that load on a charge. An AC generator produces a good sine wave and is a lot cheaper. Even bypassing your problem of 50 Hz which should not be overlooked, the real solution is a LP refrigerator which uses about the same amount of energy to do the same thing. It is quite convenient for MH and Campers though. I know that this is not what you want to hear. Ice is also a good energy storage source and people who want to avoid LP camping in this country choose to plug into the mains at campgrounds. My engineering jobs took me through a stint with Gas refrigeration, other types of refrigeration, and solar. No easy answer yet.

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