What voltage does your generator run at?

[TomSeller]

Where does Honda rate as far as clean regulated power... do you get what you pay for?

My friend is a Harbor Freight Junkie... every month he makes the trip to Harbor Freight and their generators cost a fraction of Honda.

There should be a Percent Total Harmonic Distortion rating %THD. I don't know how the HF ones are rated well or not. I have not been able to find a generator listing by model/manufacturer and the corresponding %THD

 

[joefromga]

The small 2000 peak predator inverter generator that is like the Honda is very nice and quiet. You can have a conversation with it running right next to you just like the Honda. It holds a little more fuel and will run longer as well. On sale it was 449 I think. I like it.

 

[ultrarunner]

Even less in my latest Harbor Freight promo...

 

[CobyRupert]

P=IE .... Power in watts = Current in amps times Energy [ voltage ]

JerryK was right on the formula. The pump only takes 1,056 watts to stay running, but it takes several times that many watts to START the motor.

The "E" (voltage) referred to above stands for "electromotive force", not energy.

Energy is the total amount of work.
Energy would be the Power (P) x the (elapsed) time(t). Example 10 watts supplied for 10 hours is 100 Watt-hrs (as your utility charges, or 360,000 Watt-seconds, or 360 kilowatt-seconds, or 360 kilo-Joules)

 

[Zerk]

The important thing is the ' cycles per second '. Voltage is really somewhat meaningless measurement, which varies with load, and only has to be in a certain range. Even your house voltage varies depending on how much current you, your neighbors, and the other folks around you are using. The electric company attempts to place a voltage on the high side of your residential transformer that will give you a certain range of voltage going to your house. But the cycles stay at 60 per second. They make meters to set up generators by measuring the cycles per second... which is what you are changing by adjusting the motor RPM...

110 is low. Not saying you can't get buy if you have to. But if you are getting that from the utility you should complain.

Voltage is not meaningless.

 

[Oldpath05]

The math is easy... Volts x amps = watts...

SO, 220 volts x 4.8 amps = 1,056 watts...

SR

Now your talking down to my level, I get that, thanks......

 

[Zerk]

The math is easy... Volts x amps = watts...

SO, 220 volts x 4.8 amps = 1,056 watts...

SR

Divide that by .85 to .9, to account for power factor. Watts is a resistence, like heaters and incandescent bulbs. Motors are inductive. Utilities switch in capacictors to bring up voltage, because it is important.

 

[Zerk]

Voltage does make a difference. You may need tol install an auto transformer or buck and boost to get 208 to 240, when running heat.

 

[Larry Caldwell]

Thanks, I dont know how you got the answer but that's ok, now I know what the running watts are, surge is probably a 1000 more.......

Inrush on starting your well pump would be more like 4 kw, but 240v. motors start very quickly. As long as the voltage does not drop way off, it would be up to speed in half a second. Your generator picks up a bunch of stored energy from the rotation of the armature and the motor, which gives you a mini-flywheel effect. That's where the peak wattage comes from in your generator rating. The motor may not put out enough horsepower to deliver 10 kw, but the generator will do it for a second while loads come online. The surge is too brief to pop breakers or smoke the wiring.

 

[Larry Caldwell]

Divide that by .85 to .9, to account for power factor. Watts is a resistence, like heaters and incandescent bulbs. Motors are inductive. Utilities switch in capacictors to bring up voltage, because it is important.

Motors have starting and running capacitors to compensate for phase shift.

 

[techman]

Motors have starting and running capacitors to compensate for phase shift.

Actually motors use capacitors to produce a phase shift, not correct it. The phase shift is needed to start the motor, or increase starting torque, and increase torque under load.

Also stated earlier that capacitors are used by utilities to increase voltage is also not correct. The capacitors are to improve power factor, which is in simple terms bringing voltage and current closer into phase with each other.

Watts = Volts x Amperes x Power factor (true power). Volts x Amperes are known as VA. You will see most generators will have a Watt and VA rating, which are rarely the same.

Paul

 

[buickanddeere]

Motors have starting and running capacitors to compensate for phase shift.

The phase shift during starting is momentary. As for power factor correction while running? Close enough is considered good enough, with 0.90 PF is usually the closest to unity with the exception of window airconditoners which are close to 1.0 PF to eliminate lagging reactive current from circulating through the supply breaker . Leaving the breaker's current capacity to perform work instead of circulating reactive power that loads components but performs no work.

 

[TomSeller]

Well I got around to setting the Gillette generator. I found a manual online that said to set speed of the engine so the voltage is 124V and frequency 62. I set the mechanical governor to get 124V and the frequency read 63 on my Fluke. It doesn't have any adjustment other than the governor. I'd like to test it under load and I'm thinking electric space heaters would be easy.

 

[Zerk]

Motors have starting and running capacitors to compensate for phase shift.

The power grid is running about .85


Capacitors are for starting, not power quality. You have no idea what you are talking about.

You need to learn about vars.

 

[Zerk]

Actually motors use capacitors to produce a phase shift, not correct it. The phase shift is needed to start the motor, or increase starting torque, and increase torque under load.

Also stated earlier that capacitors are used by utilities to increase voltage is also not correct. The capacitors are to improve power factor, which is in simple terms bringing voltage and current closer into phase with each other.

Watts = Volts x Amperes x Power factor (true power). Volts x Amperes are known as VA. You will see most generators will have a Watt and VA rating, which are rarely the same.

Paul

Capacitors raise voltage. You know a little.

Power companies charge for watts not vars. But they cannot change your consumption .

During the day transformers raise taps to keep voltage up. They will also switch in caps. At a big city they may have genetation export vars or try correct power.

Caps are vars one way inductors are the other.

You can take 600v inductive furnace, around pf. 3 and add caps to bring it up 1400 v, and .9 pf.

 

[Zerk]

Well I got around to setting the Gillette generator. I found a manual online that said to set speed of the engine so the voltage is 124V and frequency 62. I set the mechanical governor to get 124V and the frequency read 63 on my Fluke. It doesn't have any adjustment other than the governor. I'd like to test it under load and I'm thinking electric space heaters would be easy.

I don't work with little stuff. 63 hertz to me sounds like an awful governor. But it may not be. It may be typical.

Your load will drag it down. But it is at 63 when.lightly liad r c I take it. The grid is at 59.999. 59.997 will start shedding g load. But it may not matter at your house. You are doing an open change over.

I would be curious what other generators do. Your house as an island is a lot different. They are concerned about a load dragging it down.


Years ago I said buy this generator kw was enough. They started a small garage size air compressor and it didn't like it.

 

[dadster4]

I don't work with little stuff. 63 hertz to me sounds like an awful governor. But it may not be. It may be typical.

Your load will drag it down. But it is at 63 when.lightly liad r c I take it. The grid is at 59.999. 59.997 will start shedding g load. But it may not matter at your house. You are doing an open change over.

I would be curious what other generators do. Your house as an island is a lot different. They are concerned about a load dragging it down.

Years ago I said buy this generator kw was enough. They started a small garage size air compressor and it didn't like it.

What is little stuff?
The generators at work put out 12470 volts, two at 1825 KW and one at 3165 KW :shocked:

 

[Oldpath05]

The power grid is running about .85


Capacitors are for starting, not power quality. You have no idea what you are talking about.

You need to learn about vars.

I think this guy might be another one that dont know what vars is, or he's a slow learner. >>>>>> http://wgme.com/news/local/maine-man-accused-of-stealing-power-from-cmp-again

 

[Zerk]

What is little stuff?
The generators at work put out 12470 volts, two at 1825 KW and one at 3165 KW :shocked:

Small stuff.

It is not so much the voltage. 600 MW generators, generate at 13kV.

I have worked with 2MW diesels cats. Nice back up generation. Little hydros and some tiny steam is under 3MW too.

 

[Zerk]

The math is easy... Volts x amps = watts...

SO, 220 volts x 4.8 amps = 1,056 watts...

SR

This works for heaters, not motors.

Motor name plates have pf. Think of it kinda like efficiency. 1 is best. Divide by .85 or pf to get amps.


Google power triangle. Right triangle. resisistance, it is just a line, 0 degrees, pf 1. Watts = Volt Amps, VA. Inductors and caps add to the vertical legs, one up,one down, opposite. VA gets bigger, hyptoneuse, watts get smaller, adjecent. zero angle hyptoneuse equals adjacent. Vertical = horizontal leg of right triangle.

Transformers are rated in VA. You should do all your panel and service sizing in VA. Heaters and lights bulbs, are about the only thing measured only in watts. Everything else has an inductive or capacitive portion.

Since the hypotenuse is getting bigger so are the amount of amps. Flat line, zero degrees, less amps. Voltage is constant.