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Generator and freezer problem

  1. Sep 21, 2004 #1
    I just hooked up a mitsubishi mge 4000 generator (i live in grenada and hurricane ivan destroyed the country). the problem is that the generator worked for 12 hours and none of the water in a deep freezer that i have was frozen (the water just got cold). Everything else works fine in the house even the computer that i am using now but the freezer just doesn't seem to work properly. What could be the problem?
  2. jcsd
  3. Sep 21, 2004 #2


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    I don't know how exactly that generator works, but is it possible that the generator is only supplying one phase to your house?
  4. Sep 21, 2004 #3


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    You have the latent heat of fusion to take into account - it might take X BTUs to get the water to 32F but it takes another Y BTUs to turn it into ice. Depending on what temperature you started with, Y > X because it takes a lot of heat energy removal to cause the phase change.

    You could use a smaller quantity of water, the freezer is able to push out XXX BTUs of heat per hour and that small quantity will take a shorter time to transform to ice. A larger quantity will take longer. In a disaster, a couple blocks of ice every hour seems better than a whole freezer full of ice in 2 days.

  5. Sep 25, 2004 #4
    This is very true because ice trays make ice cubes much faster now and i am using them more now. another thing is first i sent the output for the gerator to a power outlet (a 220V socket) then the power went around the ciruit. i changed this, so now the power from the generator goes straight to the main box with the circuit breakers and so on. i don't know if resistance has something to do witht the first case. i don't have the manual for the generator so how can i know if it is one phase or two phase.
  6. Sep 27, 2004 #5


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    220V is going to be two phase. Each of those two phases is 180 degree out of phase with the other so while they are 110V to the common wire they are 220V across them.

    Inside the circuit panel the circuits are placed to try to distribute the load across the phases evenly. Otherwise if you only place a majority of the load on one of the two phases....well you can imagine. :)

  7. Sep 27, 2004 #6
    What I'd have to suspect is too much load for the genset. Do some wattage calculations as a couple of lights and an electric water heater is about all this unit can probably handle. If you have a water heater, try turning it off. I know very well from experience with generators of this size you should be able to hear the heavy loads as they burden down the engine.

    Good luck.
  8. Sep 28, 2004 #7


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    In case it is relevant:

    I don't know how the generator is configured but the typical residential voltage in the US is NOT 2 phase. The 240vac in the household is obtained via one of the secondary windings of a delta configured transformer. That winding is center tapped to obtain a neutral wire or common conductor. Each hot leg to neutral will measure 120 vac. Hot leg to hot leg will measure 240vac.
  9. Sep 30, 2004 #8
    well boulder head i am sure that the load isn't too much because although it is capable of supporting 4000W right now it is only at about 2000 max (i specifically chose not to use the heater and microwave). Geniere you have some excellent points because some of the things that you said are some of the things that have been bothering me. For one the generator seems to be designed for the U.S. in that emphasis is placed on 120V and no place on the generator it says 240V just like that; there is an outlet on it for 120V and one for 120/240V (why couldn't it just be 240V). Secondly there is a place on the generator to connect a neutral wire (that is not connected at the moment) I don't know if it has anything to do with the situation. I must say though after altering where the generator's output to the house went it seems like the refrigerators are operating better.
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