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-   -   1 phase generator feeding a 2 phase transfer switch (http://www.diychatroom.com/f18/1-phase-generator-feeding-2-phase-transfer-switch-1536/)

MAP40 12-28-2005 08:54 PM

1 phase generator feeding a 2 phase transfer switch
 
Hello everybody! I got a simple question, and I was hoping somebody could help me. I got a generator pannel at my house that I used with a 4KW genset, through a 220/4 wire connection. The genset switch has 10 circuits, five using each phase. Now I have a 4KW generator with a single phase (1 110 outlet, 30 amps). I thought of wiring the gorund and the neutral (white and green) straight, and the hot (black) to the hot of both phases (black and red) in the twist-lock of the genset switch panel. I don't run any 220 appliances on this circuits, so the 110 would be fine.
Thinking my reasoning would work, I wired everything up, but when I plugged it in the panel switch, the GFCI on the generator cut off. I checked all the connections, and everything is fine. I used a different sources (a 1500W inverter) and it doesn't work either. Is my reasoning way off?

Cape8p 12-30-2005 05:44 PM

If you have a GFI plug on the generator
the grounding will follow a different pattern than standard
based upon how the transfer switch is wired

I'm not an electrician, but they will chime in, someday

mdshunk 12-30-2005 09:49 PM

Quote:

Originally Posted by Cape8p
I'm not an electrician, but they will chime in, someday

I decided a day or so back when this question was posted that I would not respond.

Some people are beyond hope.

Two phase power has not been distributed since the 1920's. Any surviving two phase generators after that time were phase converted to 3 phase distribution. The last two phase generator, installed at Niagara Falls, went offline a few months ago.

tpile 12-30-2008 04:16 AM

Quote:

Originally Posted by MAP40 (Post 6908)
Hello everybody! I got a simple question, and I was hoping somebody could help me. I got a generator pannel at my house that I used with a 4KW genset, through a 220/4 wire connection. The genset switch has 10 circuits, five using each phase. Now I have a 4KW generator with a single phase (1 110 outlet, 30 amps). I thought of wiring the gorund and the neutral (white and green) straight, and the hot (black) to the hot of both phases (black and red) in the twist-lock of the genset switch panel. I don't run any 220 appliances on this circuits, so the 110 would be fine.
Thinking my reasoning would work, I wired everything up, but when I plugged it in the panel switch, the GFCI on the generator cut off. I checked all the connections, and everything is fine. I used a different sources (a 1500W inverter) and it doesn't work either. Is my reasoning way off?

From Terry: It is apparent that the second line connection of the red wire to the single phase genset is be sensed as a loss of current to Black wire circuit (or visa-versa) and will cause a GFI to trip. As you may be aware that a GFI senses current loss and will trip. The solution will be to either change GFI to a regular recpticle if itis safe to do so or disconnect the red wire.

InPhase277 12-30-2008 06:51 AM

Just for the record, even 240 is still single phase.

You have a bonding problem. The neutral is bonded to the frame of the generator and the green wire. The neutral at the panel is also bonded to the ground. When you hook the generator in, you establish a parallel path for neutral current to bypass the GFCI on the generator and it trips. You need to either find a way to switch the neutral at the same time you switch the hots, or disconnect the neutral/ground bond at the generator.

CowboyAndy 12-30-2008 09:44 AM

Quote:

Originally Posted by MAP40 (Post 6908)
Hello everybody! I got a simple question, and I was hoping somebody could help me. I got a generator pannel at my house that I used with a 4KW genset, through a 220/4 wire connection. The genset switch has 10 circuits, five using each phase. Now I have a 4KW generator with a single phase (1 110 outlet, 30 amps). I thought of wiring the gorund and the neutral (white and green) straight, and the hot (black) to the hot of both phases (black and red) in the twist-lock of the genset switch panel. I don't run any 220 appliances on this circuits, so the 110 would be fine.
Thinking my reasoning would work, I wired everything up, but when I plugged it in the panel switch, the GFCI on the generator cut off. I checked all the connections, and everything is fine. I used a different sources (a 1500W inverter) and it doesn't work either. Is my reasoning way off?


MAP40, your setup needs to be redone, period. Stop screwing with electricity like its nothing. The "whats it gonna hurt to try" mentality doesnt fly here.

Call an electrician, you are over your head.

For the first time in history, I agree with what MDShunk says.

jbfan 12-30-2008 09:50 AM

You guys do know this thread is 3 years old!

TazinCR 12-30-2008 09:59 AM

In Phase how do you draw a 240 single phase sin wave? Just curious because every sin wave I have seen shows each phase out either 180 degrees or 120 degrees for 3 phase.

Wildie 12-30-2008 03:00 PM

Seeing as this thread is long dead, I will use it to voice my pet peeve! Its in reference to the poles in a single phase service as phases! (plural). Why is it so difficult to drop these incorrect references. It must confuse the day-lights out of those who are attempting to become knowledgeable about their home electrical system.

InPhase277 12-30-2008 04:51 PM

Quote:

Originally Posted by TazinCR (Post 204300)
In Phase how do you draw a 240 single phase sin wave? Just curious because every sin wave I have seen shows each phase out either 180 degrees or 120 degrees for 3 phase.

The two hots on a single phase 240 are 180 degrees out from each other just like the poles of a battery are 180 from each other. That is, they are equal, but opposite. But it is still one sine wave, not two.

CowboyAndy 12-31-2008 07:23 AM

Quote:

Originally Posted by jbfan (Post 204296)
You guys do know this thread is 3 years old!

I blame tpile... he bumped it...

:whistling2:

Wildie 12-31-2008 11:10 AM

Quote:

Originally Posted by TazinCR (Post 204300)
In Phase how do you draw a 240 single phase sin wave? Just curious because every sin wave I have seen shows each phase out either 180 degrees or 120 degrees for 3 phase.

The sine wave for 240 volts is identical to the one for 120 volts! The only difference is the amplitude of the voltage. They are both 0 volts at the beginning, but at 90 degree's the voltage for 240 is greater. At 180 degrees, they are both at zero. At 270 degree's they are both negotive, but of different amplitude. Finally, at 360 degree's they are both at zero again.

AllanJ 01-01-2009 07:38 AM

(copied from another forum from a two year old thread)

Another way to think of single phase versus two phase:

Single phase: Draw a two headed arrow.

Two phase: Draw two two headed arrows that cross in the middle symmetrically (at 90 degrees).

Three phase: Draw three two headed arrows that cross in the middle symmetrically.

(60 Hz) AC motors make use of both the upper and the lower halves of the 60 Hz sine wave to provide torque 120 times per second per phase. This does not depend on (single phase) having two hot wires plus neutral or two hot wires without the neutral or just one hot wire plus neutral. In the last case the motive power (push-pull) is represented by the double headed arrow but you can use a single headed arrow to represent the power and circuitry: neutral and one hot.

All three phase systems use three hot wires, not six. You can if you wish use three single headed arrows in a symmetrical pattern to represent this. Again, there are 360 applications of torque per second (60 Hz) in a 3 phase motor making the three double headed arrows meaningful.

By the way, do not connect single phase motors that utilize neutral as well as two hots to two legs of a 3 phase system.

>>> ... how do you draw a 240 volt ... sine wave ...
With the amplitude (undulations) twice the height but the frequency the same (represented by crossings of the center line the same distance apart) relative to a 120 volt sine wave shown on the same piece of paper.


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