Need Help With Home Generator Problem

Site Notices

TNVC Partners With Envision Technology - MARS Rangefinder Family, MARS-Lc!

[ARCHIVED THREAD] - Need Help With Home Generator Problem

Posted: 9/25/2005 1:04:54 PM EDT

We are trying to run a 5000w generator during power outage (Hurricane Rita). This is a gasoline powered generator.

The problem is that the 120 volt outlets are putting out WAY too much voltage (150 volts at fast idle, wel lover 200 at full throttle). I'm assuming that there is some kind of faulty voltage regulator, but the schematic in the owner's manual doesn't show a voltage regulator. The manual does show a capacitor in the alternator, but I don't know what its function is.

Any generator experts here ??

Posted: 9/25/2005 1:07:11 PM EDT

[#1]

Many generators have a 220/110V switch that you choose your output voltage with.

Could this be it?

Posted: 9/25/2005 1:15:14 PM EDT

[#2]

You shouldn't be adjusting engine speed, it's a governed system. You need 60 hz and you'll only get it at one engine speed. Sounds like you've got a 220 genset running at an odd RPM.

99% of the time it should be running at 3600 rpm, unless it's a big set which are usually 1800.

Posted: 9/25/2005 1:15:27 PM EDT

[#3]

I have limited generator experience. But...

Shouldn't the engine speed remain relatively constant? If the engine RPMs change, the frequency of the ac sine wave (60Hz) would also change.

My generator runs about 1/3 to 1/2 throttle without load. When loaded, the governor tries to maintain a constant engine RPM in order to keep the loaded frequency constant even though the armature load tries to slow down the engine.

It sounds like someone messed with your base throttle setting and the governor isn't working properly.

Posted: 9/25/2005 1:19:45 PM EDT

[#4]

Quoted:
You shouldn't be adjusting engine speed, it's a governed system. You need 60 hz and you'll only get it at one engine speed. Sounds like you've got a 220 genset running at an odd RPM.

99% of the time it should be running at 3600 rpm, unless it's a big set which are usually 1800.

Sound like this is the problem. Then engine should remain at the same RPM reguardless of the load on it, unless it has some kind of wierd rectifier setup in it like a car's alternator, but I don't ever recall seeing anything like that. Doesn't mean such things don't exist though.

Can you provide the make and model of the generator? That might help some of the more knowledgable people here (myself excluded) in the diagnosis.

Posted: 9/25/2005 1:34:29 PM EDT

[#5]

Generator is a Devilbis GB5000. Engine is Briggs & Stratton (not that this matters).

I have owned other (Honda) generators whose engine speed varied with the electrical load (every time we would plug in another appliance, it would speed up). But in all cases, the voltage never varied.

I was assuming this should be the case with the Devilbis.

Still needing help.hinking.gif

Posted: 9/25/2005 2:19:12 PM EDT

[#6]

I've cross posted this in our ARFCOM surivival forum. Your thread is here Need Help With Home Generator Problem, as posted by dawg23 in GD forum

Come and visit us ARFCOM survival forum. We've got a generator FAQs tacked there.

Posted: 9/25/2005 2:29:17 PM EDT

[#7]

Be sure it is grounded properly.

Brad

Posted: 9/25/2005 2:32:42 PM EDT

[#8]

On your model RPM controls the voltage and frequency. The throttle or governor could be loose or the adjustment off. It's where I'd look first and probably the only thing you can adjust or fix yourself.

ETA: It should produce the correct voltage at 3600 RPM.

Some of the high end Honda's have built-in inverters so they run at different RPMs. The Devilbiss GB5000 should stay at 3600 RPM no matter what the load. The governor should keep it there. Also make sure it is set for 120v and not 240v.

Posted: 9/25/2005 2:48:33 PM EDT

[#9]

Are you reading the voltage with a true RMS volt meter or one that reads peak-to-peak.

Big difference.

Posted: 9/25/2005 3:05:24 PM EDT

[#10]

You either have a faulty governor, or an internal problem in the genset. I'd suspect the governor, after testing the internal capacitor.

Engine speed remains cnstant, throttle setting will be automatically changed to maintian RPM.

If you don't know how to fix it, I'd take it to a generator shop.

Ops

Posted: 9/25/2005 3:46:35 PM EDT

[#11]

Quoted:
Some of the high end Honda's have built-in inverters so they run at different RPMs.

Good call Robert 2011, I've seen one or two of those Hondas in the past, but I think you might goofed on your terminology. I think I goofed too when I said some have wierd rectifier set ups. I guess it would have to have both a rectifier and an inverter if the alternator were turning at a rate other than that needed to produce 60 Hertz.
For the record, alternators produce alternating current.
an inverter turns DC to AC
a rectifier turns AC to DC.

Posted: 9/25/2005 3:51:08 PM EDT

[#12]

You should have paid extra and got a Honda with an inverter. The power output is extremely clean sine wave. Clean enough to run electronics and sensitive stuff on it. We had a cheap one and it would surge and cause all sorts of problems.

Posted: 9/25/2005 6:53:56 PM EDT

[#13]

Are you keeping the 120 and 240 separate?

[ARCHIVED THREAD] - Need Help With Home Generator Problem

General » General Discussion

Win a FREE Membership!

Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!

You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.

Warning

Confirm Action

About AR15.COM

Stay Connected

Newsletter

Contact Us