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1 phase generator feeding a 2 phase transfer switch

11K views 12 replies 10 participants last post by  AllanJ 
#1 ·
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?
 
#3 ·
Cape8p said:
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.
 
#4 ·
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.
 
#5 ·
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.
 
#6 ·
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.
 
#9 ·
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.
 
#13 · (Edited)
(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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