Motor power factor assumptions
Motor power factor assumptions
(OP)
I need to assume a power factor for a 4160V motor and for a 600V motor - what are acceptable values?
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Motor power factor assumptions
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RE: Motor power factor assumptions
RE: Motor power factor assumptions
If you are about to apply static power factor corection, do not apply it based on an assumption. You must be very careful not to correct to more that 80% of the magnetising current if you are permanently connecting the capacitors to the motor circuit and using the same starter to control both.
For bulk correction and voltage drop calculations, then the assumption is fine.
The power factor can vary considerabley depending on the size and speed of the induction motor.
Larger motors tend to have a much lower magnetising current (down to 20%) than small motors (up to 60%). Two pole motors have a lower magnetising current than 8 pole motors and submersible pump motors tend to have a high magnetising current.
Best regards,
Mark Empson
http://www.lmphotonics.com
RE: Motor power factor assumptions
Best to ya,
Old Dave
RE: Motor power factor assumptions
4160 Volts is used for large motors, 300 HP and above. Use PF 0.85 to 0.90
600 Volts is used for medium size motors 50HP to 500 HP, use PF 0.85 to 0.88