Can my 067680 voltage be adjusted? it quits generating powerafter 10 min. unit keepsrunning and voltage flucuates and doen not generateload

Why generators do not generate electricity

1. Fault phenomenon

When the generator set speed reaches the rated speed, the AC exciter stator excitation circuit switch is closed and the voltage regulator is adjusted to the maximum value when the generator speed reaches the rated speed.

2. failure cause
The generator core remanence disappears or is too weak, the newly installed unit is disturbed by long-distance transportation or the generator is placed for too long, the generator core remanence disappears or the remanence inductance is weak, which results in the generator remanence voltage vanishing or less than the normal remanence voltage value. That is, the remanence voltage is less than 10 V, and the remanent phase voltage is less than 6 V. Because of the stator, rotor and AC exciter stator of synchronous generator, the core of rotor is usually made of 1mm-thick silicon steel sheet, which is subjected to vibration after excitation, and the remanence magnetic field is easy to disappear or weaken.

Output voltage is based on 3600 rpm @ 60Hz. Sounds like your generator is over speeding slightly. Put a Frequency meter on the output of the generator and tune it to 61.5 Hz, that will get your generator in the 3600 RPM range.

Is it putting out that voltage with or without load? Speed will influence these units, depending on the model the capacitor regualtor in the back end of the alternator is subject to this error. If you have an AVR then it mayeb adjustable depends on the unti you have. Try measuring engine rpm to be sure it is withing specs first. That is not so high a voltage as it can be 10% of nominal. I am sure it drops down under 1/2 load, then all is ok

Can you manually adjust the voltage on the generator without load?? If you have 120/240 60hz output on it and you are not overloading the unit (amperage), then it may be as simple as adjusting whats called your gain setting for your voltage regulator. Obviously you are seeing what happens when it is set too low. Trying raising that setting until it becomes unstable then back it off. Unstable meaning voltage starts jumping all over.

Hi and welcome to FixYa. I am Kelly. Since you did not mention the make or model number of your generator I will respond in generic terms. If your generator is at 127 volts with NO load it is adjust at the very top end of the manufacturers limits. There is a 10% tolerance so 120 VAC + 12 is 127 VAC. Under an electrical load above 500 watts the generator should drop the output voltage slightly so your generator would still be within factory limits. Personally on any generator as a repair person; I set the output voltage at 126 VAC no load so that when the user puts the generator to work the output voltage is good. If your generator is running at 127 VAC under load then you can adjust the governor screw on the governor plate CCW about 1/2 turn to drop the voltage. Without a generator model number or engine number I can not tell you exactly where the governor plate is on your engine / generator. The screw will have a lock nut that you must loosen 1/4 turn then turn the adjustment screw CCW to drop the voltage. Just make sure to re-tighten the lock nut when the adjustments are complete. Mind you by decreasing the output voltage you also drop the output freqency at the same time you decrease the output voltage. It is better to have 125 -127 VAC under a no load condition as the more electrical load you add the more voltage drop you will notice. It is best to adjust the generator to 122.5 -123 VAC under a medium load. (50% of output capacity) A bread toaster is 1400 - 1600 watts and is a good load for a 3000 watt generator. Also a good hand held hair dryer will use around 1600 watts. If you use this type of load and the voltage output is 122.5 to 123 VAC I would not adjust anything. I have been working on generators since 1970 so this is nothing new for me. I hope that you understand everything I posted. If not, feel free to ask as many questions as you wish in any future response.
Thanks for choosing FixYa,
Kelly

It is always good to have the voltage set down by a small percentage and so the setting you have is quite good because most devices work happily with a lesser voltage than a higher one except those consuming higher currrent.
Now if you set the generator for the higher rating with the connected load and when the device is not used the voltage will rise above and may damage sensitive equipments. So take this tip.

Could be any of the following: high voltage spark coil,ignition control box or the coil(s) under the flywheel/generator in the engine.Outside chance of a bad wire.
You can use the liquid spray from a can of "air in a can" upside down to cool the HV coil and ignition box to see if that will let the machine start right after it quits but use caution around the cooling spray as it will freeze skin and eyes fast.
You may also want to try and get a service manual and do the electrical resistance measurements on the above parts to see if they are out of spec when unit quits and then have a good dealer verify the part as good or bad but this is not an exact science.Also test with several meter as some will give you different reading of the some item.

it sounds alot like it is producing alot more power than 120 volts per leg you should really only have plus or minus 10 percent of that voltage anymore will blow lights check voltage output with meter, if voltage is high may have problem with voltage regulator and it may need be replaced. I assume that not all of the lights in the house are on the same circuit therfore not on the same leg of the generator so is probably only one leg of generated power to high there for only blowing some of the lights

coil may be breaking down or earthing out as vibration over time can wear out the insulation on the wire

You may have a 'TEST" mode on your Generator. Ten Minutes is usually the duration of the 'Exercise' function of most units, so I'd like to determine what mode you are starting your generator in. Please comment.