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Mojogosrving's avatar
Mojogosrving
Explorer
Feb 23, 2020

Generac GP3300 modifications

Hello all,
I am really disappointed with my generator. did not know the watts were spit and it wont even run my microwave in my rv. my microwave wattage is 990w. should of been plenty if it were 3300 watts. but instead, it is 1600. my gen surges when micro is on, then eventually the breaker trips.
Is there any way to bypass the split so that the gen will run on the full 3300 watts?
Thanks for any advice!!
  • Sometimes
    The output wiring from the generator head connections
    Can be changed from (center tapped series 230v Split load )
    To (parallel 115v only full power)
    You are still limited to circuit breaker limit going to that duplex outlet

    Need to see the wiring diagram and a picture of the wiring from head to terminal block to outlets

    It has been done before, depends on the generator

    It's strange that 1600 Watts won't power your MW
    Did you check the fridge is on propane
    And that the converter is off and not charging the batteries, also some water heaters have an electric option
    Everything that can use propane instead of electric
    Should be set to propane, Not electric or automatic
  • Is the cooking power of your micro rated at 990W? If so then the power used could easily be 1500~1600 watts overall.
  • From one Wiz to another ...

    MrWizard wrote:
    Sometimes ...

    Not likely. The stator on alternating current generators is wound with one continuous wire that is center taped. This is a single phase that is "split", hence the term split phase.

    I don't know enough about "electric power generation" (not covered in any of my EE courses) to know if you can simply "fold" the second half of the wire back on to the first half.

    I guess you could test this if you had a good meter (oscilloscope would be better) by ...

    • Start the generator, turn the fuel off and run the carburetor bowl dry
    • Connect L1 to L2 on the 240V outlet
    • Remove the spark plug (zero compression)
    • Pull the cord as hard as possible
    • If you are reading close 120V then you should be good.

    If there is any type of electronic voltage regulation it could be a problem !
  • Old wizard its very common construction

    All 4 leads of the two windings, are brought out of the head ,
    L1 is one hot leg L4 is the other opposite hot leg
    L2 & L3 are tied together as the neutral
    Even Onan does this

    L1 to L4 is 230v

    Connect L1 & L3. Together
    Connect L2 & L4. Together
    The windings are now parallel

    115v full ouput

    L1/3 is used as the hot

    L2/4 is used as the neutral

    Will have to move a circuit breaker wire from L4 to L3 to parallel the breakers or one breaker will be in the neutral side of output
    Can also replace the two separate breakers with one larger one
    Depends on what breakers and sockets/outlets are mounted in the generator face plate
  • If it is surging now, putting windings in series for full output as 120VAC is not going to change anything. Get engine running and governed smoothly and your microwave will probably be happy.
    Art.
  • Edit above reply to correct for a senior moment. change SERIES to PARALLEL :o
    Art

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