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Robearbam
21-08-2002, 11:42 AM
On a refrig that operates on 120 VAC or 12 VDC... Do they use a converter to run the compressor when it's under 12VDC? Thanks for any input on this ... I have to look at one for a friend and it'll be the first. :(

frank
21-08-2002, 08:19 PM
I suspect that the comp is rated at 12v dc and when connected to 120v it goes first through a transformer and rectifier.

Never seen one and only speculating :)

superheat
22-08-2002, 03:54 PM
I have only seen them with 115 volt compressors. A friend of mine says the one in his RV has a 12 volt compresser.

sherrieeg
22-08-2002, 04:28 PM
I am looking for Engineers with strong cascade refrigeration design experience. Please send resume's with "Cascade Design Engineer" in the subject line to: smcdonald@eegrp.com.


Thanks
Sherri

Johann Prinsloo
29-08-2002, 08:13 AM
Danfoss makes a 12v / 24v DC compressor. Check their web at http://www.danfoss.com/Compressors/products/r134a_12-24v_dc/index.htm.

Hope this will help.
Johann Prinsloo

:)

Gibson
30-08-2002, 04:53 AM
Around here the 120 VAC / 12 VDC would be an RV refrigerator with dual voltage heater.
It should be mentioned that we are probably talking about an absorbtion refrigerator... No compressor.

Robearbam
30-08-2002, 11:16 AM
This particular unit does have a compressor. I know it runs on 120 Volt but the 12 VDC is nada. I'm not sure if the compressor is suppose to run on the 12 VDC side. but I do know it does not get cold on 12VDC. I am assuming the power supply is bad because everything works okay on AC. Absorption? Is it possible this thing operates two different ways? :confused:

Gibson
31-08-2002, 05:16 AM
Never seen a combination absorbtion/dx system but hey... More information would help a lot. Make, Model and Serial number? Dimensions?

condenseddave
02-09-2002, 05:39 AM
Originally posted by Robearbam
This particular unit does have a compressor. I know it runs on 120 Volt but the 12 VDC is nada. I'm not sure if the compressor is suppose to run on the 12 VDC side. but I do know it does not get cold on 12VDC. I am assuming the power supply is bad because everything works okay on AC. Absorption? Is it possible this thing operates two different ways? :confused:

Is this an underslung truck refrigeration unit? If so, there are most likelt two compressors, and the 12VDC is for the fans and controls only.

One compressor under the hood, under engine power, the other under the truck chassis, under shore power.

Robearbam
03-09-2002, 11:15 AM
Actually, this is an RV frige ... made for boat, camper etc. It was the power supply by the way. They do use a converter as part of the power supply. Sort of the same thing as one of those converters that work in a car ... ya know ... 12 VDC and you can run a small appliance 120 VAC depending on the wattage of the converter. So ... the compressor runs when 12 Volt is powering it but it's 120 Volts delivered to the compressor.:cool: