line to line and line to neutral circuits

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keep PMs as PMs?

That's funny. I pretty sure that there is no forum rule stating that if someone PMs you you cannot reply in a thread.

Was the post deleted because of the word "ass" ?
I honestly wasn't aware it was a forbidden word.
 
I deleted the tread for the reason I stated, you can also add that it did add to this discussion.

If you have a problem with a PM someone sends you I urge you to either ignore it or notify a moderator via PM.
 
Twoskinsoneman said:
If the load increases on the motor it would draw more current and thus the voltage across it would drop and the voltage across the other motor would rise. But as the voltage dropped wouldn't the current also drop, sort causing some sort of balance?
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Remember that the current is the same everywhere in a series circuit.
 
Excuse my ignorants
I havn't been on line for a while.

I see three motors wire in parallel with two ungrounded conductors.

I thought a MWBC refered to a multi wire branch circuit, and the neutral being the factor making it a multi wire circuit?

Are straight 208,240and 480 volt circuits refered to as multi wire?

Isn't it just one two wire circuit? :-?
 
motor.gif

The current goes up, the voltage goes down, and the horsepower increases.
 
That straight line with the arrowhead is called the load line, which depends on the impedance of the other motor. As you can extrapolate it will eventually cross below the const HP curve, then the HP decreases. Eventually the motor stalls. It still has lots of torque (where the load line crosses the I axis) but no HP because it isnt moving.
 
Twoskinsoneman said:
That is a good point. Describe electrically (like I tried too :roll:) what you think would happen if one of the two identical motors started getting loaded down more than the other.
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Okay.

As the mechanical load increases, the impedance decreses (which is why a motor's current rises with load.) The voltage across this motor will drop, and the voltage across the lesser-loaded motor will rise.

The same thing happens with unequal light bulbs: the higher-rated bulb's impedance is lower, so its share of the voltage drop is less. The lower-rated bulb is the one that pops from over-voltage.

A neutral's current varies about zero as the loads on each side turn on and of and/or increase and decrease. This current is from the neutral's attempt at keeping its voltage at zero, relative to the utility's neutral.
 
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