X-No-Archive: Yes

I constructed a bench test circuit like this

http://img379.imageshack.us/img379/9690/motorcct0pq.png
An unloaded 3/4 hp motor is connected to the power source with a 25'
length extension cord.
The current draw is 8.84A. When I measure the voltage drop across the
neutral conductor, it is 2.0V and since the wires are in pair, 2.0 x 2
=4V. I calculated the resistive loss in the extension cord to be
8.84A x 4.0V = 35.36 watts

Strangely, when I measure the voltage at the motor end and the source end of the extension cord, the difference is only 1V. Taking power readings at both ends, the difference is 37watts, which is consistent with my previous math. If the power lost in the wiring is 37W and the current is 8.84A, then the voltage drop should be around 4V, but somehow, the voltage drop is only 1V and 3V is getting cancelled out. The inconsistency does not happen with a resistive load.

Explanation?

I constructed a bench test circuit like this

http://img379.imageshack.us/img379/9690/motorcct0pq.png

Strangely, when I measure the voltage at the motor end and the source end of the extension cord, the difference is only 1V. Taking power readings at both ends, the difference is 37watts, which is consistent with my previous math. If the power lost in the wiring is 37W and the current is 8.84A, then the voltage drop should be around 4V, but somehow, the voltage drop is only 1V and 3V is getting cancelled out. The inconsistency does not happen with a resistive load.

Explanation?