I don't know much about 3 phases motor... I would like to know if I could measure the power developped (or output power) by a 3 phase motor with these data:

60 HZ, HP = 10.0, S.F. 1.15, V = 575, A = 10.2, RPM = 1750, Type TEFC, IP = 55, IC = 411, Phase 3, Raiting = Cont, Ins.Cls F, Amb = 40° C, Rated load 100%, Nom. Effic. 89.5

and measurement of current (ex.: I1 = 5.1, I2 = 4.8, I3 = 5.2)

Regards

ML

 

Current measurement without concurrent phase-to-phase voltage measurement, especially when determining "actual" load, can be misleading!

What are the corresponding ph-to-ph voltage measurements?

Do you want to know actual load with, or without, the benefit of
electrical instrumets?

Regards,
Phil Corso, PE
Boca Raton, FL
[[email protected]] ([email protected]) {[email protected]}

 

ML,

There are several electrical equations that might be helpful to you. Here are a few:

V=IxR
P=1.73xVxIxPFxEff
HP=P/746

where V=Voltage
I=Current
R=Resistance
P=Watts
1.73=SQRoot 3 (for 3 phase motors)
PF=Power Factor as decimal or Cosine of phase angle of current vs voltage
HP=Horse Power

Hope that helps you.

Bob Waterfield
Nucor Steel Berkley