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Skidus1's avatar
Skidus1
Explorer
Jun 27, 2018

Generator adjustment

I got my old 3500 watt Coleman gen out to run it a bit and checked the voltages. I only use it to run ac or make coffee. I adjusted the Hz to 60 under the ac load and I have 117 volts on the gen outlet and 109-110 on the inside trailer outlets. When I turn the ac off the voltage on the gen goes to 133 and hz to 63.8. Question is should I adjust hz under load or no load. I did it under load. The hz dropped to around 57 after ac was turned on when I set it to 60 hz. Thanks
  • Someone gave my son a Honda powered off brand generator which I replaced the carb on and got it running. The Hertz and voltage fluctuated so much that I put it on CL to get rid of it. I considered it probably ok if someone wanted to run some lights and circular saw in a pinch but I wouldn't power anything I value. I set the Hertz/ rpm and the voltage dropped so low that my PD EMS cut out when I turned on the AC. If I adjusted it up the voltage was also 135 or so. It was 4500 watts and sold it for $150.

    The only good thing was that for $38 on Amazon I got a spark plug, carb, recoil starter, air filter, oil, fuel valve, ignition coil, shut off switch. Oh oh oh, it also came with a metal gas cap to replace the plastic one on my sons Eb3000 (?) Honda which the squirrels at Disney campground had chewed on.

    How can we buy all that and get free shipping? Slave labor with an AK pointed at them.
  • Sounds like that gen is in need of serious repair, and, not something anyone wants to be near at a campground.
  • No expert here but on my Onan Emerald 4000 I adjust the frequency without a load to about 119-120 VAC. Once the load is applied the governor should adjust the engine as needed. Might try it without load and see what it does when you turn on the A/C. Also there are pivot points on the generator that you can add a drop of oil to in case it is hanging up. I usually see a drop off to about 115 VAC when I turn on the A/C. Hz may fluctuate a little but no more than 2 -3 HZ continuously. Momentarily the HZ may fluctuate even more but that could just be noise on the AC.
  • IIRC both Onan and Champion
    used 62Hz no load seting

    63hz is not going to hurt your coffee maker or your TV etc...

    you want 59-61 for the A/C
    if you 60HZ for A/C thats good,
    but that 133v is a TAD high
    that coleman does NOT have an electronic voltage regulator
    i think i would adjust it to 59 with the A/C
    and see what all the numbers are with and with out the A/C
  • This gen never sees a campground it’s only when I’m in the mountains dry damping. I know it’s loud and why I have 200 watts of solar and use it when the wife wants coffee or it’s very hot. Getting a new trailer in the next few years so not wanting to buy a gen I use maybe once a year. Next one will be built in ??
    The voltage of 130’s is just when I turn the ac off. Air on voltage is 110 at 60 hz.

    So set to 62 hz at no load and call it good? Thanks for the reply’s.
  • Hoping to get a happy medium on the settings. Using a Killawatt meter plugged into the gen I have 126 volts and 61 hz no load. With 15k ac on I get 111 volts and 57.8 hz. Thoughts on that adjustment?

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