Line Current for 30kW 3 phase motor

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 14K views
p75213
Messages
93
Reaction score
0

Homework Statement


Calculate the line current required for a 30kW 3 phase motor having a power factor of 0.85 lagging if it is connected to a balanced source with a line voltage of 440V.

Homework Equations


P=√3Vl*IlCos ∅
Il=[itex]\frac{P}{√3VlCos ∅}[/itex]


P=Average Power
Il=Line Current
Vl=Line Voltage
∅=∅v-∅i=∅Z


The Attempt at a Solution


Il=[itex]\frac{30000}{440√3\times0.85}[/itex]=46.31A

The answer given is 50.94A
 
Physics news on Phys.org
NascentOxygen said:
http://img7.imageshack.us/img7/8738/p0813.gif

That's what I thought. This book has plenty of errors. Although it hasn't stopped me from learning a lot.
 
Last edited by a moderator: