Sewage Pump Motor Selection
Sewage Pump Motor Selection
(OP)
I have a simple question. If a BHP is at certain level say 100 HP; and motor efficiency is say 93%; I always assumed that the motor rating should take in account the motor efficiency: in this case 100/0.93 = 107.5 HP. If the motor is rated: say 105 HP (the numbers are just for an example) does that mean that the motor will be slightly overloaded? All these years I thought that it would be and you should have motor with the rating higher than its shaft power, but the pump manufacturer is trying to convince me that that is not the case. Am I wrong to insist that the motor be rated > 107.5 HP. We are talking about the design point, where pump would run most of the time. Thanks for your help





RE: Sewage Pump Motor Selection
Steve
RE: Sewage Pump Motor Selection
A centrifugal pump always operates on the pump curve. As the pump moves to the right on the curve (higher capacity@ lower head), the required HP increases with pumped flow.
As the curve moves to the right, notice that the HP increases. That is what is meant by overloading the motor. You must install the HP on the right side of the pump curve if your pump is capable of operating there.
The HP needs to be such that you do not overloading the motor.
RE: Sewage Pump Motor Selection
RE: Sewage Pump Motor Selection
form at the motor shaft.
Motor losses are the difference between the input and output power. Once the motor efficiency has been determined
and the input power is known, you can calculate output power.
This brochure should help you:
http://
RE: Sewage Pump Motor Selection