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Re: Only if...
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Re: Only if... ()

Bill Howatt
I'll try to explain it but I'm afraid I may cause further confusion!

The two hots are connected to the same source one hot at each end of a transformer winding (on the pole outside supplying your house) and thus are indeed part of the same circuit. To go a step further, the neutral wire is connected to a tap in the center of the this transformer winding which provides the 110V from the center tap to each hot. Because the hots are on each end of the winding, giving 220V between them, they are out of phase by 180 degrees.

Regardless of what you may plug in between each hot and the neutral there is still a path back through the other hot if there is a load connected to it.

When dealing with 110V circuits we normally don't worry about this and just think of it as the current going back on the neutral wire when in reality, it is only the difference current, if any, between the loads on each hot that goes onto the neutral. The other portion of current that you think goes down the neutral is cancelled out by the out-of-phase current coming from the load on the other side. The "neutral current" from each hot does indeed add but since they are out of phase, it actually is a subtraction. For example: +10 plus -7 (minus since out of phase)=3A down neutral conductor.

All of the circuits in your panel work this way and just like the case of a single load on each hot to neutral, the only current that goes out the big neutral back to the pole transformer is the difference between the total load current on each side of the panel.


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