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11-29-2012, 09:22 PM   #16
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Quote:
 Originally Posted by Missouri Bound Yeah....it's the same, but your description and explanation is totally inaccurate.
How so?

 11-29-2012, 09:24 PM #17 Member     Join Date: Apr 2011 Location: Almost Arkansas Posts: 2,764 Rewards Points: 2,000 We're done. You aren't grasping this and it's not up to me to teach you. __________________ Do you want it your way or the right way?
 11-30-2012, 06:38 PM #18 Member   Join Date: Oct 2012 Location: Lansing,MI Posts: 194 Rewards Points: 196 Watts / volts = amps 12000w/240v=50a output
 The Following User Says Thank You to HVACTECH96 For This Useful Post: Missouri Bound (11-30-2012)

11-30-2012, 10:17 PM   #19
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Quote:
 Originally Posted by Missouri Bound We're done. You aren't grasping this and it's not up to me to teach you.
Sorry if I aggrevated you. I thought this was a DIY site to share knowledge. All I'm saying is what the above poster said, but for 120VAC loads.

12000W/120VAC=100A

11-30-2012, 10:32 PM   #20
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Quote:
 Originally Posted by diystephen Sorry if I aggrevated you. I thought this was a DIY site to share knowledge. All I'm saying is what the above poster said, but for 120VAC loads. 12000W/120VAC=100A
I'll try again. The generator does NOT provide 12kw @ 120v. It provides a total of 12kw @ 240 volts. Let me give you an example. Lets say you own two cars which each can go 120 MPH. That does not mean you can go 240 MPH. Back to the generator. You have 50 amps available at the generator for a 120v load. The wiring for the generator will be calculated at that amperage. I see that you are arguing semantics. Good for you, but this is an electrical forum and there are certain facts which apply in any answers or discussion here. The best thing we can do here is make the answers simple and proper within the guidlines of the NEC.
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11-30-2012, 10:42 PM   #21
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Quote:
 Originally Posted by Missouri Bound I'll try again. The generator does NOT provide 12kw @ 120v. It provides a total of 12kw @ 240 volts. Let me give you an example. Lets say you own two cars which each can go 120 MPH. That does not mean you can go 240 MPH. Back to the generator. You have 50 amps available at the generator for a 120v load. The wiring for the generator will be calculated at that amperage. I see that you are arguing semantics. Good for you, but this is an electrical forum and there are certain facts which apply in any answers or discussion here. The best thing we can do here is make the answers simple and proper within the guidlines of the NEC.
Ok, let me give it another shot. I understand that the genny is @ 240VAC. That 240 comes out of a dbl pole 50A breaker. A device using 240VAC is limited to 50Amps and no more. That dbl pole 50A breaker is just 2 50A breakers connected together. When using 120VAC loads that dbl pole can supply 50A on each phase. Since 120VAC is phase to neutral you can draw 100A.

If there was only 50A available at the genny for 120 loads you would get this:

50A * 120VAC = 6000 W

Then genny is rated for 12000 W

I did a quick search and there are a few threads detailing this. Here's one:

Maybe they can explain it better than I can.

11-30-2012, 11:46 PM   #22
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Quote:
 Originally Posted by diystephen Ok, let me give it another shot. I understand that the genny is @ 240VAC. That 240 comes out of a dbl pole 50A breaker. A device using 240VAC is limited to 50Amps and no more. That dbl pole 50A breaker is just 2 50A breakers connected together. When using 120VAC loads that dbl pole can supply 50A on each phase. Since 120VAC is phase to neutral you can draw 100A. If there was only 50A available at the genny for 120 loads you would get this: 50A * 120VAC = 6000 W Then genny is rated for 12000 W I did a quick search and there are a few threads detailing this. Here's one: question about a generator amperage Maybe they can explain it better than I can.
I will make a simple shorthand answer here to clear up the confusing with the generatours .,, It is the same way with transfomers !!

So let me post the photo what it look like .,

Now U1 and U2 is your 240 volt connection now next step the unmarked centre post is a netural so the netrual to either U1 or U2 is 120 volts.

Now look at the winding so let use the example as one poster say 12 KW ok now each set of coil or winding is 6 KW each side so on 120 volts you can draw up to 6 KW which that is 50 amp on each side., Again this is on 120 volts I will expain next on 240 volts .,

Now with 240 volts you have U1 and U2 connected together so the result is 240 volts and you will get full 12 KW which the pair of 6 KW windings are connected in series which the voltage and wattage will increase but not the amparage it will stay the same.

Now you can understand why when you run the generatour mode you have to watch the load and balance them much as possible to keep it running smooth and get the most of the KW rating of that unit.

Hope that help here.

Merci,
Marc
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 The Following User Says Thank You to frenchelectrican For This Useful Post: diystephen (11-30-2012)
 11-30-2012, 11:58 PM #23 Engineer   Join Date: Nov 2012 Location: Chicago Posts: 191 Rewards Points: 161 Thanks frenchelectrician. The drawing is a much better way to illustrate 50A on each phase than my explanation
12-01-2012, 12:08 AM   #24
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Quote:
 Originally Posted by diystephen Thanks frenchelectrician. The drawing is a much better way to illustrate 50A on each phase than my explanation
Diystephen.,

Pas de problme .,, ( not a problem )

This what I taught some of my customers when they were gripping with issue with generatour loading and tripping breaker(s) so it is a common item I have to expain in simple term with a good drawing that will useally clear up the situation.

There are few generatours that can be reconferated to full 120 volts which some case it called full power slection, very limited numbers of generatours will have this feature. that I called parallel connection so you can use full rated wattage of the unit.

Merci,
Marc

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The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )

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