Generator question

[Gary Fowler]

Power in Afganistan was 50hz. We had to reset clocks weekly or so. At a few minutes a day it doesnt typically show up for a quick test though.

At $35 a Kill A Watt is probably the easiest best bang for your buck option to check frequency. It does volts too. Amps, but that's only through the 1 outlet. https://www.amazon.com/dp/B000RGF29Q/ref=cm_sw_r_apa_i_QdDREbJW996VD

We had the same thing in one of the African countries I worked. 50 hz makes 50 minutes per hour on the clock, so after 10 hours of actual time lapse your clock will be 1hour and 40 minutes faster.

 

[Diggin It]

At $35 a Kill A Watt

$25 at HF: "Kill A Watt"™ Electric Monitor

 

[Oldpath05]

Even commercial power will fluctuate 115-120 V, nothing wrong with your genset. You could up the throttle setting a bit to compensate if you want to get it in the ball park. As for heating elements like coffee maker, just about any current would work for them. 5 volts shouldn't make much difference on speed of use on heating elements, motors would be a few RPM slower but not enough to notice without something really accurate measuring the RPM.

My power only varies from 119-120, my Generac will not power my micro, toaster coffee maker etc without moaning and gowning, 113-114 volts is not enough, there is something wrong in paradise.

 

[Oldpath05]

Plug in clocks,,,,,,,,,,,, who still has plug-in clocks, the only one I have are on the gas cook stove and my wife unplugs it every night. 50hz 60hz, there is no hz reading on my multi meter, I havent got HZ clue of what the HZ thats all about, if I get 120 volt reading on my muti meter then thats all the HZs I'm gonna worry about. I never heard all this hz stuff 40 years ago, I am going hz crazy, I heard that..........

 

[LouNY]

We had the same thing in one of the African countries I worked. 50 hz makes 50 minutes per hour on the clock, so after 10 hours of actual time lapse your clock will be 1hour and 40 minutes faster.

I would expect it to be an hour 40 minutes late, as you said it's only going to advance 50 minutes every hour.

 

[Industrial Toys]

Man, I hated every second of school. Nothing they could tell me interested me in the least. BUT, I was very interested when they occasionally made the school room clocks go around at a fast rate to set the proper time. Why they couldn't have had a lesson on that system, to me now, is beyond me.

 

[BrokenTrack]

Are you guys sure you got the frequency calculations right? The last time I had a generator run, it was 91 hours without power, and I noticed the clocks were off by 15 minutes or so everyday. From the way the microwave and refrigerator was running, it seemed like the frequency (also called hertz) was low, not high.

At the time, my PTO generator only had a voltage gauge, so I would throttle it up to put it at 220 volts, but I had no idea what it was running for amps or hertz. Fluke makes a multimeter that shows frequency, BUT it does not work on generators accurately because of the electromagnetic forces they give off.

I decided to change that and bought a control panel. It shows amps, voltage and frequency. It cost me $180, but good gracious, that is nothing compared to ruining the motor on a refrigerator...or the motor down at the bottom of my well. Just the work alone to replace that pump would be a pain to say the least. The key thing to keep in mind is, hertz cannot be off at all. It has to be within + or - 2 hertz, and ideally at 61 hertz so when loads hit, and the governor kicks in, there is no shortage.

Since installing it, I found the voltage here via grid power is pretty high, at a constant 245 volts, with frequency at a steady 60 hertz.

You can see my control panel here in the upper, right corner of the photo: a 100 amp switch with frequency, voltage, and amps.

 

[BrokenTrack]

I looked into clocks and frequency, and found it kind of interesting. It was completely circular.

In order to generate quality power, a man in the 1930's invented a clock for his power plant that derived time by frequency, so that plant operators had steady hertz for output. Within a year or two, almost every plant used his clock to generate clean power.

Then the clock companies realized they could use the frequency, to set clocks. Today, a tiny computer chip that costs a few cents to make, tells time. My clock is set by the atomic clock, but it that just determines the time after a power failure. Its time is then calculated by that tiny computer chip after that. They make computer chips that set their own time, but they cost $1 to make, so the clock companies still use the old method of using frequency to tell time.

I guess why pay more money when you can tell time for free using the utility company?

In that regard, the utilities tried in 2009 to stop having to adjust frequency for the time, but they lost out. The Federal Government now forces them by law to adjust the frequency of the power so that clocks are right.

 

[Diggin It]

Since installing it, I found the voltage here via grid power is pretty high, at a constant 245 volts, with frequency at a steady 60 hertz.

That's not high. That gives you each leg at 122.5 which is 'normal (115-125). Constant and steady is what you want.

 

[shaeff]

I finally decided to check the outlet voltage on my 20 year old 7000w Generac generator this past weekend while in middle of all day use. I knew it wasn't and never did put out 120v because it wouldn't run my microwave, toaster and coffee makers always took longer, I put the volt meter on outlet at the the generator and in house, the readings was 114-115 volts.

So I guess this summer it's time to update it to something that will put out 120 volts, on the assumption that they do make generators that does put out 120 volts, 119 probably would be close enough.

View attachment 651159 View attachment 651158
PS I wonder if this is a ghost thread...................................

Have you checked the capacitors (if equipped?) and the engine RPM? I have a Porter Cable H1000ISw, it's 10k, 19.5k surge. It's got a 20hp Honda motor on it. When I first got it, the output was low- around 108v. It ran great, but didn't *sound* right. So I checked engine RPM, it was low. A quick adjustment back up to 3600rpm and it puts out 120v/60hz.

Easy enough to check, might save you money, AND even get you a new tool out of it.
(new tool= laser RPM gauge)

 

[Oldpath05]

Have you checked the capacitors (if equipped?) and the engine RPM? I have a Porter Cable H1000ISw, it's 10k, 19.5k surge. It's got a 20hp Honda motor on it. When I first got it, the output was low- around 108v. It ran great, but didn't *sound* right. So I checked engine RPM, it was low. A quick adjustment back up to 3600rpm and it puts out 120v/60hz.

Easy enough to check, might save you money, AND even get you a new tool out of it.
(new tool= laser RPM gauge)

I didn't think it's possible to adjust RPMs on a governed set motor. It sure sounds like a fast idle motor to me any faster and it might throw a rod, as fast as that motor is going it should easily be putting out 118 volts, 113-114 is not right.

 

[shaeff]

I didn't think it's possible to adjust RPMs on a governed set motor. It sure sounds like a fast idle motor to me any faster and it might throw a rod, as fast as that motor is going it should easily be putting out 118 volts, 113-114 is not right.

On mine it is, all it took was a quick turn of a screwdriver and it was good to go.

I wasn’t sure if that would do it but it’s been perfect ever since. Might be worth it to grab a infrared tach and check how fast she’s spinning.

 

[BrokenTrack]

I didn't think it's possible to adjust RPMs on a governed set motor. It sure sounds like a fast idle motor to me any faster and it might throw a rod, as fast as that motor is going it should easily be putting out 118 volts, 113-114 is not right.

There has got to be a way to adjust it, even at the factory they have to adjust them for RPM and thus frequency.

The cheaper they are, the more they would have to be adjustable to change from places that operate at 60 hertz, or 50 hertz.

 

[RoyKing]

look for the manual online for a governor run version of the motor it will tell you how to adjust

 

[Oldpath05]

On mine it is, all it took was a quick turn of a screwdriver and it was good to go.

I wasn’t sure if that would do it but it’s been perfect ever since. Might be worth it to grab a infrared tach and check how fast she’s spinning.

Mine is way way way way above idle to the verge of full throttle, I cant imagine why any manufacturer making a generator that has to run full throttle. Seem so half throttle should be plenty of RPMs, if not then maybe a bigger generator is needed but seems to me any and all generators should already be set by the manufacture and shouldn't have to be fiddled with. There has to be a generator somewhere by someone that right out of the box puts out 120 volts without fiddling with...............

 

[Fallon]

Mine is way way way way above idle to the verge of full throttle, I cant imagine why any manufacturer making a generator that has to run full throttle. Seem so half throttle should be plenty of RPMs, if not then maybe a bigger generator is needed but seems to me any and all generators should already be set by the manufacture and shouldn't have to be fiddled with. There has to be a generator somewhere by someone that right out of the box puts out 120 volts without fiddling with...............

The more poles in the generator, the slower it can spin. But that means more parts & more copper required. So cheap generators use the minimum number of poles & flog the engine to make a cheaper product. With people wanting a cheap backup generator, this method gets the job done with a minimum of cost. It doesnt make for a super long lasting or quiet generator, but they generally aren't used that frequently.

You could gear up the engine to get output RPM. But again at the low end it's super price competitive & the cost of gears or whatever puts that manufacturer at a big disadvantage.

Changing Generator Rotational Speed has some more info. But a 2 pole generator needs to run at 3,600 rpm where a 4 pole only needs 1,800 rpm. So generally any generator engine will need to spin at one of those RPMs.

 

[Sawyer Rob]

I've also seen the cheaper gensets that were running too fast, right out of the box new!

A friend bought one, plugged it into his moms house (through a transfer switch) and every light that was on, blew out the bulb.

Back in the box it went, and was replaced with another, that WAS set at the right RPM.

SR

 

[Oldpath05]

The more poles in the generator, the slower it can spin. But that means more parts & more copper required. So cheap generators use the minimum number of poles & flog the engine to make a cheaper product. With people wanting a cheap backup generator, this method gets the job done with a minimum of cost. It doesnt make for a super long lasting or quiet generator, but they generally aren't used that frequently.

You could gear up the engine to get output RPM. But again at the low end it's super price competitive & the cost of gears or whatever puts that manufacturer at a big disadvantage.

Changing Generator Rotational Speed has some more info. But a 2 pole generator needs to run at 3,600 rpm where a 4 pole only needs 1,800 rpm. So generally any generator engine will need to spin at one of those RPMs.

POLES!!!!!!!!!!!!!!!!!!!! I couldn't even understand HZ now poles. I think the next generator I buy will be from HD, I'll bring it home, fire it up check for 119-120 volts, plug my micro and coffee maker in it and if I get coffee just like from the power company, it's a keeper, if not back to no hassle return HD it goes then on to the next brand.

 

[grsthegreat]

POLES!!!!!!!!!!!!!!!!!!!! I couldn't even understand HZ now poles. I think the next generator I buy will be from HD, I'll bring it home, fire it up check for 119-120 volts, plug my micro and coffee maker in it and if I get coffee just like from the power company, it's a keeper, if not back to no hassle return HD it goes then on to the next brand.

Home depot is not so friendly on generator returns anymore. Too many people buy them during outage then return them later. Our HD has sign up that says no returns, defects have to be sent to factory. Not Sure who gets stuck with shipping. Seems like a bother to me.

A 4 pole alternator is quite large and heavy and requires a larger engine to turn for same amount of power as a 2 pole. Most 4 pole units use automotive engines for larger units. I had an old Onan 5,000 watt 4 pole ....was a monster. And not really all that quiet. But ran forever.

 

[Sawyer Rob]

I had an old Onan 5,000 watt 4 pole ....was a monster. And not really all that quiet. But ran forever.

I still have one, it's a heavy beast!

SR