# How to power fridge with inverter?



## cobb (Apr 20, 2005)

During the last power failure from hurricane gaston I had no power for two days. I tried to run my standard freezer over fridge with a 300 watt inverter and it tripped it imemdiately. I had hoped to power it for any amount of time to help extend the lift of food I have in there. I then tried a 450watt inverter that auto reset and it kept looking like it wanted to work, then it would trip and reset. 

I was wondering, how much power would one need to to run a fridge or an estimate? 1000 watts, 750?


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## LitFuse (Apr 20, 2005)

The problem is the surge amperage drawn at startup. My fullsize fridge runs on about 2A, but it takes about 10 times that (for a second or two) to start the compressor.

Peter


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## BatteryCharger (Apr 20, 2005)

800 watt coleman inverters are pretty easy to find for $50. I don't know if it will start your fridge, but I have two of them and they work pretty well for small power tools. The surge current is over 13 amps.


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## VidPro (Apr 20, 2005)

agrees with what they said, compressor is hard starting.
tried to get my full size going with a 1500, what a joke.

they have "motor capacitors" on various hard starting motors, got one on the HVAC compressor here.
i dont understand how it helps, because its AC, but that is what they do.
IF its a very small frige, and did not have them, AND you upgraded your inverter lots, and that didnt work, you might research how these motor starting caps accomplish anything.
they sell them surpluss at the surplus electronic places online.


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## Starlight (Apr 20, 2005)

I copied some data from a generator site during the last round of hurricanes in Florida. I was purchasing an inverter for the same reasons. The site info says that a refrigerator/freezer is 500 watts running and 2000 watts surge. I ended up buying a 3000 watt inverter. I think all the inverters I looked at had 150% surge capacity over their rated capacity. That would mean you need a 1250-1500 watt inverter.


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## Kilted (Apr 20, 2005)

I personally have a 5kw inverter grid-tie/backup, 24kwh battery bank, and 5.2kw solar panels to keep it all going.

For a less ambitious project look into using two large deep cycle AGM marine 100-250 amp hr in a 24 volt configuration. Using a xantrex prosine inverter: http://www.xantrex.com/web/id/42/p/1/pt/8/product.asp these two models have built in chargers and transfer relays. The chargers will handle gell cells and agm batteries, with multistage charging, i.e. they automaticlly switch from fast charge, slow charge and float depending on battery condition. The loads are connected all the time. While the grid is up the load will be running from the grid. Upon grid failure the transfer relay will switch the load to battery in less than 1/2 cycle (<16ms).

This inverter CAN NOT be used to drive the grid for sell back.

For grid connected battery backup sell back using solar panels I recommend only two vendors Beacon Power http://www.beaconpower.com/products/SolarInverterSystems/M5.htm or Outback Power http://www.outbackpower.com/ The best source online for info is HomePower Magazine http://www.homepower.com/

-- Kilted


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## cobb (Apr 21, 2005)

THanks, I had no idea I would be looking at a thousand watt inverter or so. I may hold off on that idea for now. 

The capaciator idea is interesting. I see those on larger motors for compressors and what not and even my folks blower in their ac unit. Infact they had to replace that as it blew fuses at one time and since they did, the lights no longer blink when it starts up. If I recall correctly they attach it in parallel to the lines to the motor and somehow it lessen the load for it to start.


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## eluminator (Apr 21, 2005)

I'm not sure what you mean by capacitor idea. Single phase AC motors use capacitors to get started. They create a second phase that gets the motor spinning. After the motor gets up to speed, they are switched off. The centrifugal switches that do this also go bad.


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## Pydpiper (Apr 23, 2005)

[ QUOTE ]
*Kilted said:*
I personally have a 5kw inverter grid-tie/backup, 24kwh battery bank, and 5.2kw solar panels to keep it all going.

For a less ambitious project look into using two large deep cycle AGM marine 100-250 amp hr in a 24 volt configuration. Using a xantrex prosine inverter: http://www.xantrex.com/web/id/42/p/1/pt/8/product.asp these two models have built in chargers and transfer relays. The chargers will handle gell cells and agm batteries, with multistage charging, i.e. they automaticlly switch from fast charge, slow charge and float depending on battery condition. The loads are connected all the time. While the grid is up the load will be running from the grid. Upon grid failure the transfer relay will switch the load to battery in less than 1/2 cycle (<16ms).

This inverter CAN NOT be used to drive the grid for sell back.

For grid connected battery backup sell back using solar panels I recommend only two vendors Beacon Power http://www.beaconpower.com/products/SolarInverterSystems/M5.htm or Outback Power http://www.outbackpower.com/ The best source online for info is HomePower Magazine http://www.homepower.com/

-- Kilted 

[/ QUOTE ]

Wow, you take this very seriously.. /ubbthreads/images/graemlins/smile.gif


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