Generator question

[AndyMA]

115 is not abnormal. Typical range is 110-125VAC

Check your in house outlets while on utility power and see what you're getting.

ANSI Standard for Grid Voltage is =/- 5% 114V - 126V

Andy

 

[LouNY]

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.

They are a bit heaver but require no more horsepower per KW then a 2 pole,
most engines are larger and heavier to make an equal amount of HP at lower rpm.

 

[grsthegreat]

They are a bit heaver but require no more horsepower per KW then a 2 pole,
most engines are larger and heavier to make an equal amount of HP at lower rpm.

?.. what. An air cooled 22 kw (3600 rpm 2 pole) uses 999 cu in engine(36 hp) while same 22 kw liquid cooled (1800 rpm 4 pole) has a 2.4 liter engine.(50hp )
The alternator is at least 50% larger in size if not more....i never actually measured them.

An engine running at 1/2 speed requires twice the torque. A 4-pole motor has about 3.0 ft-lbs of torque per horsepower whereas a 2 pole motor has 1.5 ft-lbs of torque.

So to turn a 4 pole alternator at a slower speed will require a larger engine.

 

[LouNY]

?.. what. An air cooled 22 kw (3600 rpm 2 pole) uses 999 cu in engine while same 22 kw liquid cooled (1800 rpm 4 pole) has a 2.4 liter engine.
The alternator is at least 50% larger in size if not more....i never actually measured them.

It does not take HP to spin the generator head until it has a kw load at that time the hp requirement is the same it doesn't matter how many poles in the generator,
roughly 2 hp per kw of produced power.
Look at the rated hp of those two engines at the operating rpm.

 

[grsthegreat]

It does not take HP to spin the generator head until it has a kw load at that time the hp requirement is the same it doesn't matter how many poles in the generator,
roughly 2 hp per kw of produced power.
Look at the rated hp of those two engines at the operating rpm.

36 hp vs 49-50 hp

 

[BrokenTrack]

The thing is, you have to account for the power curve of whatever engine you are using. With gasoline engines, the power curve is a little less in RPM then diesels...

I ran into this trouble, because my PTO generator has to be meshed to the gear box. This is fine for PTO operation, but not so great for my diesel engine only configuration. If I ran my Perkins Diesel Engine straight into my PTO generator, my engine would only be turning 900 rpm or so, and thus my 55 hp engine is only making 8 hp at that speed. That is not enough wattage for my electrical needs, and nearing stall speed if a heavy electrical load was to hit it.

But to get the right hertz, which is 60 cycles at 245 volts, it has to be geared up. I need at least 1500 rpm to start getting into its power curve of my Perkins engine, and a higher rpm would be better (2000 rpm). So for me, I need a 7.5 inch pullet at the flywheel of my Perkins, and a 20 inch pulley at my pto generators input shaft to give me the 1800/540 rpm that I need.

But then there is the issue of governor speed. EVEN if an engine could make enough power at 900 rpm, that is below 1200 rpm, and that is when the governor stops working effectively. If the water pump to my home was to come on while the generator was operating at 900 rpm, the engine would not throttle up, and I would get brown-out...or low hertz (also called frequency). Eventually this will burn up my well pump.

So everything really is tied together. It is not just about having enough horsepower, it is having enough horsepower at the right rpm.

 

[Oldpath05]

I didn't see anything about poles or HZ on this one but did see 120/240 volts, but what happen to the surge number, has peak and running, comes with transfer switch hook up but I already have 7000 watt transfer switch. The best part it comes with a 10 year warranty for New England TBN members...........
https://www.homedepot.com/p/Westing...tch-Outlet-for-Home-Backup-WGen7500/301466616

I did a quick 120 volt check tonight in several outlets cause someone hear mentions volt variances, yup got some variances tonight, cant get a 120 volt reading like I have in the past, could be some UFO inference going on............

 

[BrokenTrack]

I didn't see anything about poles or HZ on this one but did see 120/240 volts, but what happen to the surge number, has peak and running, comes with transfer switch hook up but I already have 7000 watt transfer switch. The best part it comes with a 10 year warranty for New England TBN members...........
https://www.homedepot.com/p/Westing...tch-Outlet-for-Home-Backup-WGen7500/301466616

I did a quick 120 volt check tonight in several outlets cause someone hear mentions volt variances, yup got some variances tonight, cant get a 120 volt reading like I have in the past, could be some UFO inference going on............

View attachment 655413 View attachment 655412 View attachment 655411

I have noticed CMP has some varying voltages/hertz lately.

 

[RoyKing]

Westinghouse went bankrupt years ago, the name was bought up by some China company. The same one that screwed up the nuclear power plant build in Ga. I don't believe much in the ad. 16 hr run time at what load? Three year warranty hah you won't be able to get parts. My gut feeling China junk.

 

[grsthegreat]

Westinghouse went bankrupt years ago, the name was bought up by some China company. The same one that screwed up the nuclear power plant build in Ga. I don't believe much in the ad. 16 hr run time at what load? Three year warranty hah you won't be able to get parts. My gut feeling China junk.

Westinghouse is not chinese. Maybe the generators are made in china, but company is usa owned.