Generator question

     Question,
I have a 5000 watt (6250 max) portable generator with a Tecumseh 10hp flat head engine. With the generator running with no load the rpm is about 3610-3620rpm. With a heavy load on it the rpm drops to 3490-3520 rpm. Is this normal or will the lower rpm cause low voltage ????
Thanks Brian
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Brian wrote:

No built-in Volt or Amp. meter on the set? I don't think so but voltage drop if overloaded.
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The machine will try to maintain constant voltage. If it's not able to, the voltage will drop. You can check this with a voltmeter, and see if it drops to low. It should be in the range of 115-120
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It sounds like you have one similar to what I have. Most portable generators are not very voltage/frequency stable. They rely on simple mechanical governors to hold the speed constant. They should normally run at 3600 rpm to generate the 60 hz frequency and the rated voltage. Anything faster or slower will raise or lower the voltage and frequency.
Most house hold devices should be ok from about 110 to 125 volts.
I would not worry about what you are seeing and it is normal for that generator.
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Yes, and if the voltage is dropping *below* about 110 then you either have overloaded the generator or it has a Tecumseh 10HP POS engine ;-). In general these kinds of generators will put out about 125 volts with no load so if you (OP) have a voltmeter you can check it with and without load. If that's the HM100 then, if I recall correctly, you need a 3/8" open end wrench or deep socket to adjust the engine speed.
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Anything slower than 3600 will reduce the frequency from 60 hz. 3620 rpm will give you 60.33 Hz, 3490 rpm will give you 58.16. Some things are very frequency sensitive.
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Lower RPM leads to lower hertz, which likely won't hurt anything.
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3600 rpm = 60 hz 120v. No load setting to 125 or so rpm gives room for a normal swing in voltage. What is your V at 3520, you dont want to go to low as hz lowers also. There is a safe range you want to stay in. It is normal to drop and yes it lowers Voltage and Hz. Go to low or high and some things can be damaged
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