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Basic question about motor

Basic question about motor

Basic question about motor

(OP)
For a 40 hp motor with 1.15 service factor, when the motor starts to pull high amps like 52 amps, what would be the horsepower being consumed? Is it still under 40 hp like 38 hp, or it is already higher than 40 hp like 45 hp?

RE: Basic question about motor

What's your FLA?
Your loading is roughly (52/FLA)*40HP
Assuming frequency is namepalte and voltage is balanced and matches nameplate.

=====================================
(2B)+(2B)'  ?

RE: Basic question about motor

For a 40 HP motor 52 Amps will be more of an issue at 600 V than at 480 V.
If only one leg is high you may have a voltage unbalance issue. You may have a low voltage or a high voltage issue.
The motor may be working at its service factor loading.
The motor may be overloaded.
The relationship between current and HP is not linear, however, for small changes at or near full load, the relationship is approximately linear.
If the voltage is high to the point of saturation, the relationship becomes non linear quickly.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Basic question about motor

what was the voltage that supplied to the motor?

RE: Basic question about motor

HP is a relationship to torque and speed. Current generally follows HP but is not a specific determining factor because it can change with applied voltage and power factor. If you can measure Watts (or kW), that would be a better indicator of the actual shaft HP if you are interested. There are plenty of watt meter options available to do that.


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