merlynr

Member
I've been working on this army 10kw generator and tested it by hooking up to a cooking range. I had 240v and when turning on a top burner it took the load ok and also with 2 burners on. The reason I used this method is the 60hz meter seems to not function correctly. Is there a simple way to check for 60hz by induction? Do some Fluke meters have this capability? I also opened the oven door while it was hooked up and the light came on but looked a little yellow but this old range is a loaner from my friend and it may be normal.
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(quoted from post at 09:43:37 05/04/15) I've been working on this army 10kw generator and tested it by hooking up to a cooking range. I had 240v and when turning on a top burner it took the load ok and also with 2 burners on. The reason I used this method is the 60hz meter seems to not function correctly. Is there a simple way to check for 60hz by induction? Do some Fluke meters have this capability? I also opened the oven door while it was hooked up and the light came on but looked a little yellow but this old range is a loaner from my friend and it may be normal.
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ake care & be careful with electricity, but this connection to the gen & power company source will allow you to compare the frequency of the two. Two 120v bulbs in series, with 120v each from power company & from generator.
 
A devise anyone with a generator should own is a Kill O Watt meter. They are less than $20, or were last I looked. Available at
Home Depot or on line. They will monitor Hz, volts, amps and many other things. We keep ours plugged in whenever the generator is
running for a walk by check of operation.
 
(quoted from post at 07:31:53 05/04/15) A devise anyone with a generator should own is a Kill O Watt meter. They are less than $20, or were last I looked. Available at
Home Depot or on line. They will monitor Hz, volts, amps and many other things. We keep ours plugged in whenever the generator is
running for a walk by check of operation.

I saw some on ebay but didn't know if they simply plug in to an outlet or induced reading.
Thanks very much.
 
a lot of fluke and other meters have hz ability. i would not try hooking gen to utility even with a load as shown.
 
That is a phase detector, not a frequency detector.

It will work to detect out of phases, but a BAD....... idea without an interconnect agreement so the power company knows you are hooking up.
 
(quoted from post at 10:56:47 05/04/15) a lot of fluke and other meters have hz ability. i would not try hooking gen to utility even with a load as shown.
ell, then don't you do it. :twisted:
 

Not going to. That doesn't look right!! Just checking generator with isolated testing at this point.
 
The problem I found with measuring frequency is accuracy of meter. I purchased a
110v champion generator with built in frequency meter. I thought something was wrong
with that meter because is showed 65 hz. I compared it to a 6 function meter, watt-
hr/volt/ammeter and frequency which showed 60 hz. I put the 6 function meter in to
power line, same 60 hz. I used a EVOM meter from HF. Junk, the accuracy of HF meter is
+ or minus 20 hz. Then I went on ebay and did a looked up 110v frequency meters for
generators. Very cheap and very accurate. That meter showed 60 hz from power company
and 65 hz on champion genny. I trusted that frequency meter not the others.

I've posted an ebay listing for a 220v frequency meter, not sure if it's the cheapest,
not sure of accuracy either, but for under $20 I would try it. Compare it to power
company. When in college I worked at Crane navel, USNAD, in the calibration lab,
calibrating frequency meters and every electronic piece of equipment on the base.
220v frequency meter
 
(quoted from post at 11:09:23 05/04/15)
Not going to. That doesn't look right!! Just checking generator with isolated testing at this point.
our generator would not be "putting anything" back into the power company generators/system, but if you don't understand it, then you probably should leave it alone. Same goes for messing with anything that a person doesn't understand, whether mechanical, electrical or human!
 
You can't measure the phase angle between two waveforms unless they're at the same frequency. So if the lights aren't flashing, the generator is at the same frequency as the grid.

And it's really not an issue to hook the generator to the line as shown, since the line is presumably already hot. (Obviously it won't work if you open the service disconnect.)

The real problem with this setup is you're measuring the generator's no-load frequency. All generators droop under load, so if you adjust the generator's speed with no load it will be too slow when under load.
 
(quoted from post at 13:25:09 05/04/15) You can't measure the phase angle between two waveforms unless they're at the same frequency. So if the lights aren't flashing, the generator is at the same frequency as the grid.

And it's really not an issue to hook the generator to the line as shown, since the line is presumably already hot. (Obviously it won't work if you open the service disconnect.)

The real problem with this setup is you're measuring the generator's no-load frequency. All generators droop under load, so if you adjust the generator's speed with no load it will be too slow when under load.
ell,.........if you want to check gen loaded, .......put a load on it! :roll:
 
(quoted from post at 10:56:19 05/04/15)
(quoted from post at 13:25:09 05/04/15) You can't measure the phase angle between two waveforms unless they're at the same frequency. So if the lights aren't flashing, the generator is at the same frequency as the grid.

And it's really not an issue to hook the generator to the line as shown, since the line is presumably already hot. (Obviously it won't work if you open the service disconnect.)

The real problem with this setup is you're measuring the generator's no-load frequency. All generators droop under load, so if you adjust the generator's speed with no load it will be too slow when under load.
ell,.........if you want to check gen loaded, .......put a load on it! :roll:

You didn't read the thread. I put a load on it.
 
(quoted from post at 14:11:56 05/04/15)
(quoted from post at 10:56:19 05/04/15)
(quoted from post at 13:25:09 05/04/15) You can't measure the phase angle between two waveforms unless they're at the same frequency. So if the lights aren't flashing, the generator is at the same frequency as the grid.

And it's really not an issue to hook the generator to the line as shown, since the line is presumably already hot. (Obviously it won't work if you open the service disconnect.)

The real problem with this setup is you're measuring the generator's no-load frequency. All generators droop under load, so if you adjust the generator's speed with no load it will be too slow when under load.
ell,.........if you want to check gen loaded, .......put a load on it! :roll:

You didn't read the thread. I put a load on it.
DID read about your load AND MarkB's comment that the problem with my flashing/not flashing lamp scheme was 'no load', so I was simply telling him to load it if he wanted to check freq under load. That is all. Read on!
 
The real problem with this setup is you're measuring the generator's no-load frequency. All generators droop under load, so if you adjust the generator's speed with no load it will be too slow when under load.[/quote]

You didn't read the thread. I put a load on it.[/quote]

I'm picking up a KIll A WATT EZ METER from Home Depot that measure HZ so I can check the generator output.
 
Hello merlynr,

Wood a electric clock with a second hand work? Some one suggested it at one time. Stop watch 60 seconds, clock 60 seconds. Where frequency has to be exactly at 60 cycles there are governors that will have zero droop speed. They may be a bit pricey though, and possibly not made for your application. I thought that 3600 R.P.M.s under load would produce 60 cycles?

Guido.
 
JMOR/MerlynR:

My point being that if you are plugged into the line power so you can check the phase, you can't very easily apply your house load to the generator since the house is already running off the grid. I suppose you might have some way to disconnect the house from the grid while still getting power to an outlet that bypasses your main disconnect. If so, you could pull it off.

Actually, I COULD do that, because my house and shop have separate disconnects. I could use the house transfer switch to run the house off the generator, then run a cord out to the shop for the phase sense. But it's a lot simpler to plug in a twenty buck Kill-a-Watt to read the frequency and voltage.
 

remember that a engine generator will and should... read a bit high under no load and a bit low under full load and about perfect at 60 percent load... because the governor is not perfect and has trouble keep in rpms perfect.. so as it loads up, the engine speed and frequency drops a bit even though the governor is giving it more fuel. A few cycles high or low will not hurt, but you want it to be close, at load.


I would not ever hook up to city power... There is no point in worrying about if your set at the same frequency as your generator will drift way too much for any test to be useful. An intelligent inverter system can sync up with city power but is design for it.
 
I used your twin series light bulb to set gen set speed / frequency for years.
While helping a friend troubleshoot and repair a gen set that was unused for years and I suspected just lost it's residual field magnetism, we used the twin bulb setup. It instantly field flashed the generator and got it working. We then loaded the generator and adjusted the governor until the flashing almost or did stop.

I still laugh when I think of the owners comment. He said" Very cool and kind of reminds me of Vegas(the flashing lights) :)
 
(quoted from post at 17:58:22 05/04/15) I used your twin series light bulb to set gen set speed / frequency for years.
While helping a friend troubleshoot and repair a gen set that was unused for years and I suspected just lost it's residual field magnetism, we used the twin bulb setup. It instantly field flashed the generator and got it working. We then loaded the generator and adjusted the governor until the flashing almost or did stop.

I still laugh when I think of the owners comment. He said" Very cool and kind of reminds me of Vegas(the flashing lights) :)
hat was what we were taught in the Electric Motors & Generators class in college & demonstrated in lab.
P.S. By the way Bill, it isn't to sync, but rather to check to see if generator frequency is at or close to power co. frequency, which has atomic-clock accuracy & you can't afford a freq meter that good! :wink:
 
Good luck with a KIll A WATT EZ METER. Mine said 60 hz when the meter on generator
said 65 hz. Champion said they set theirs at 65 no load so it will be closer to 60 under
load. Come to find out the accuracy of the KIll A WATT EZ METER was way off, it
registered 60 hz for both 60 and 65. The best way to compare two frequencies it to use a
dual trace scope or a single trace and apply one voltage as the horizontal sweep. You
will get a perfect circle when both are the same frequency and in phase.
 
Guido,
Yes an old clock would work, but not on 220v.
The best is to use an oscilloscope, but not many of us has access to one or may have a clue how to use one. I wish I still had the one I built over 40 years ago. Better yet love to have the dual trace I had at work.

I posting a link to an oscilloscope and a Lissajous pattern. When I was in college and worked an USNAD crane we had a special radio we tuned into the national time standard, WWVC, to pick up a 10 MHZ signal we would use to calibrate The old digital counters which also had a 10 MHZ quarts clock. We used an oscilloscop and the lissajous pattern to sink the digital timer's clock.
lissajous pattern.
 
If you don't want to buy a good Fluke meter. Go buy the Kilo Watt Meter.Set the genset at 62 HZ no load. When your loads comes in it will drop a
little.Normal operating range is 57 to 63 HZ.I never did trust the meters on the military units. So I carried my Fluke with me.Never hook your
generator to your house. Unless you have a proper set up.Turning your main breaker off and using the dryer plug. Is not the proper way.

I can tell you what will happen if you try and run your house improperly.And you have a problem.
1 The power company will pull your meter and it will cost you to get it back.
2 Home insurance will be canceled.
3 You will be held liable for any damage or injury you cause.

I know because I have seen it done.
 
Cool, this Kilo Watt Meter EZ is pretty neat, I may have to get one too. At work I have a Fluke 87 multimeter and it measures frequency, but it's not a cheep meter. I'm not sure about the more affordably Fluke meters. Fluke test equipment is pretty darn good stuff, that's what the majority of our test equipment is. BUT here's another thought. Through the years with travel trailer and now an RV we have used both portable and onboard generators when "dry camping". Sometimes we ran on generated power for multiple days only shutdown for fuel or if we run out of fuel. Anyway, if you set the clock on the microwave to match the time on your cell phone you can tell if your generator is running fast or slow. If the clock logs 57 minutes during an hour accurately timed on your cell phone you would have AVERAGED 57Hz for that time period, so you could turn the governor up a smidge. I forget how I did the math but you can do the same thing after after ten hours of running your microwave time is six minutes slow this would indicate that over that 10 hour period you are running 6/600 ths slow or about 0.1% low. Something to that effect anyway. I was schooled to believe that most electrical equipment operated at or above voltage & frequency, especially motors. That being the case I keep an I on the clock and prefer seeing it gain a little bit of time instead of lose time. Just my two cents worth! Jim
 
I was also going to tell him this trick. You can also go to a good electrical supply and buy a 240 volt light bulb. It is cool when you get everything synched up. The bulb will dim out and then come up to full bright till you get it right on the nose and it stays steady. I have a Fluke 179 meter. Love it! You folks do know that a lot of military gen sets are not 60hz but are 400hz. Should tell you some where on a plate.
 
As for your thoughts on average Hz, Exactly! Due to the way mechanical governors work it is very unrealistic to expect any home
type generator to carry 60Hz from no load to full load. It can and is done with certain large and expensive sets where power needs
require it but not at a price people are willing to pay for home stand by, nor is it needed. I own a fluke, actually two of them,
used one to be certain the Kill-O-Watt meter was accurate. My wife who is about as mechanically inclined as nothing quickly
learned how to use the readings in the Kill-o-watt to monitor generator loading. We have a home built diesel powered set with
brush type generator head that is harmonically excited thus no electronic regulation, when hz varies, so does voltage. When the needs call for it she takes the
meter out to the gen shed, plugs it in and resets the throttle on the diesel. Usually this would be when the central air is on or
off, nothing else really affects the generator to any degree. We consider 58Hz the acceptable low and 62 the acceptable high.
I realize some are not up to that or don't wish to mess with it but it works for us, powers the entire house, was cheap to build
and is cheap to operate.
 
Fluke meters have changed over the years. Now even the lower priced meters have the frequency capability. Still not cheap compared to "house brands", starting about $130 or so and going up. Fluke is what everyone else has to compare to, and they are more durable as well. We sell them where I work along with two other what I call private label meter lines. Rarely do we see a Fluke brought in for warranty or repair, and when we do, they are usually abused in some way.
 
> As for your thoughts on average Hz, Exactly! Due to the way mechanical governors work it is very unrealistic to expect any home type generator to carry 60Hz from no load to full load.

I don't think this is a problem with inverter-based generators. Which is the reason I went with a Honda EU6500i for my emergency generator.
 
Hello Geo-TH,In,

One leg at the time would work? I don't think too many home use generators would need to have the 240V output@ exactly 60 cycle frequency harmony HA!HA!,

Guido.
 
Keeping everything running at 60hz is nice, and the right thing to do, but evidently it's not as critical as we think.

I once worked on an ancient British built generator. Evidently it was set up for 50hz, 200v. I puled every cover I dared to, looking for access to the governor to speed it up... I never found a way, afraid to go too deep because no parts could be found, if I broke something, it was all over!

It was used on a hunting lodge for years, ran all the usual appliances, ac, tv, refrigerator... Never had a problem with anything. Probably wasn't real efficient, but everything worked!
 
Don't waste money buying any equipment. With a simple clock with second hand and AC lighting you can tell speed of engine very precisely. Remember AC lighting is flickering at 120Hz or 7200 flickers per minute. (120 Hz because 60Hz sine wave has both a top and bottom half.) Just put a mark on engine flywheel. When running around 3600 RPM, you'll see two marks 180 degrees apart while engine is running. If the marks are perfectly steady, you're going 3600RPM. If marks are going against rotation, you know the engine hasn't made it quite half way around by time light flickered. So you know you're going less than 3600 RPM. Just time how long it takes for the marks to appear to go around. ie if they go around 10 times in a minute, engine is running 5RPM below 3600...
 
Guido,
Using a speaker and beating the two frquencies together would work only if the frequency difference were above 20 hz. Anything less than that isn't in the human audio range. Now if public service is 60 hz and the generator were at 120 hz, then you would have the first harmonic or is it overtone? Been too long.
 
The voltage can be pretty sloppy like 110 to 125 no problem. It is the frequency that needs to be on the nose. Sixty is golden for electronics and computers and high efficiency home heating systems. You blow a control board in those heaters and you are looking at about $200.oo and MORE !!!
 

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