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6.5hp Chonda engine on a NIkota 3500w Gen. It has what looks like a capacitor in it. This thing is old, so I'm guessing that's also a regulator.

Anywho, After making the repairs on this (carb mainly), I checked the voltage. From one plug, I dialed up the governor to 120v's. The other plug (same receptacle), I'm getting 129. Plug in a drill and the V increase 2 or 3 v's.

How could the same plug get two different voltage readings?

If it is an old generator and doesn't have an AVR it may have a capacitor to help keep the genny polarized. The voltage will be RPM dependent. If the voltage is different at each receptacle then pull it and see how it is wired.

PTmowerMech said:

6.5hp Chonda engine on a NIkota 3500w Gen. It has what looks like a capacitor in it. This thing is old, so I'm guessing that's also a regulator.

Anywho, After making the repairs on this (carb mainly), I checked the voltage. From one plug, I dialed up the governor to 120v's. The other plug (same receptacle), I'm getting 129. Plug in a drill and the V increase 2 or 3 v's.

How could the same plug get two different voltage readings?

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It is quite easy done if someone or the OEM did a split receptacle. I have this on household wiring over the year where I was needing up to 30 amps+ from the same receptacle using one that is a 15/20 amp unit. It basically becomes two separate circuits being fed with 240v three wire with ground that is split down into two 120v circuits. In household wiring it is common to have one half of a receptacle to be hot all the time and the other switched; hence, hence a split receptacle.

The electrician; however may be using the same 120v line to do this or not. Just depends if they want the lights or other item to stay working when one half gets tripped. I have done this here too but prefer a 240v split circuit with separate 120v breakers. Much easier than running two cables and lower cost too; just drives the apprentices crazy.

The first thing I would check would be the wiring and condition of the receptacle. Anything makes you question it, replace, their cheap. Second thing I would be checking would be the hertz on each receptacle, either 50 or 60. Can you take a picture of the ID tag, I’d like to see a breakdown of the unit. Don’t know if I’ve seen a Chanda clone on an old unit. If no ID tag, what RPMs, Hertz and Volts are you getting on the other receptacles, if there is more than one?

Just be careful replacing the receptacle since most have one leg of the winding connected to one outlet and the other leg of the winding connected to the other outlet. If you don't remove the bridge between the two outlets you will short out the windings. So check the old outlet carefully to determine if the outlets are bridged or unbridged.

ILENGINE said:

Just be careful replacing the receptacle since most have one leg of the winding connected to one outlet and the other leg of the winding connected to the other outlet. If you don't remove the bridge between the two outlets you will short out the windings. So check the old outlet carefully to determine if the outlets are bridged or unbridged.

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Exactly what I was eluding to. Here is the pictorial example:

There is only one 120v outlet. And one 220v outlet.

Well, first rattle out of the bag this morning, I fired it up, plugged in my testers and was getting 120.7 out of both plugs. Hertz was at 61.

Not sure what could've happened. The last thing I did last night was remove the gen cover, inspect the wiring and the receptacle, blew it out with air. Put everything back, rechecked and was getting the same readings. Then posted this thread.
Even the tiny bit of surging is gone this morning.

My guess is it's gonna blow up soon. LMAO. They say, they always run the best just before they take a catastrophic failure. Had a Detroit 60 do that on me once.

StarTech said:

Exactly what I was eluding to. Here is the pictorial example:

Click to expand...

I'm gonna recheck that. Even though I'm getting 120 out of both plugs this morning. It shouldn't have been getting a different reading last night. Maybe that jumper is getting thin.
All the wiring looked good.

I would warn that Frequency is much more important to watch than Voltage.

The Voltage in your home can normally vary from ~115 to ~130V depending upon power line temperature, other power consuming devices on the same line, and many other factors. This rarely has a detrimental effect on the device using the Power.

However, many, many devices depend upon having stable Frequency. Some of them (like motors) are quite dependent upon the exact Frequency. This is why most generators rotate at exactly 3600 RPM. That's what's necessary to achieve exactly 60 Hz, the standard Frequency in the USA.

When you play with the carb settings, these settings have a very large effect on the operating speed... which changes the Frequency.

The last five posts are the reason I requested the numBert of receptacles and ID tag. That wat we can try to identify how the unit is wired. As Born posted, HERTZ is much more important than VOLTAGE. If you are going to be working on generators, you better get a meter which will read Hertz. If you aren’t checking hertz before units leave your shop, you might be paying for someone’s tools which can burn up very quickly.

Most portable generators really won't exactly 60 HZ over its range of light load to full load. If the engine is setup to run exactly 3600rpm and 60HZ at no load it will be slightly lower at full load. Most portable generators usually run at about 3700 to 3750RPM at no load so that it runs at 3600 at 3/4 load.