Answer / wareagle

You can also use capacitors to create a "phantom" 3rd phase
from the other 2. This may be what you have seen, but what
you probably didn't know is that this severely robs the
motor of power capacity. The motor runs severely unbalanced
and has a lot of what are called "negative sequence
currents" because of the 1 phase power and because the sine
waves are 180 degrees apart on the 2 "real" phases,
compared to being 120 degrees out on true 3 phase. Negative
sequence current produces negative torque in the motor and
causes heating without doing useful work, meaning that it
will severely overheat under load. For this reason, you
must derate the motor by at least 50%, some even say 66%.
So that means if you have a 15HP motor, you had better not
need more than 7-1/2 or even 5HP out of it if you are going
to do this.

Answer / electrical alie

It is know form physics that you can provide water about 45
ft away. This is clear from the objective test that is run.
However when you try to sole this problem from the books
you have read, you find conflict. This is because if i
tried solve objective from the other book then i could not
solve this from the 3rd book. Therefore you must use the
motor curves that power the overload system to determine if
you unknown will operate properly. It will help if you can
determine what is standard height of an energy meter is
from ground.

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