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Question
```how we calculate the 30 KW 3phase electric motor current on
Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By

# 1
30 KW MOTOR NOMALLY FULL LOAD 54 AMPS, BUT WITH OUT LOAD
30% CURRENT WILL TAKE,ANY THREE PHASE INDUCTION MOTOR WITH
OUT LOAD 30PERSENT CURRENT WILL TAKE.

 Is This Answer Correct ? 145 Yes 35 No
J.kesavan

# 2
No load current of a 3phase induction motor varies
according to its KW and rpm. Normally as a thumb rule
fraction HP motors (below 2.2KW) will be 50% of full load
current. Above 2.2KW may be 20% to 30% OF full load
current.

 Is This Answer Correct ? 57 Yes 16 No
D.g.skandan

# 3
no standerd farmulla to calculate the noload current but as
a thumbrule 3 ph induction motor will draw 30% current on
no load but few motor will take 50 to 60 % current

 Is This Answer Correct ? 44 Yes 9 No
Suresh

# 4
Actually,there is no standard formula to calculate the
noload current of the motor.Normally 25% to 40% of full
load current of the motor.Also depending upon motor KW and
supplier..

 Is This Answer Correct ? 37 Yes 4 No
Suthan Prabhu

# 5
In=p/1.732*v*p.f

=30x1000/1.732*.8*380

=57A

Ino=57/3
19A

 Is This Answer Correct ? 50 Yes 28 No
Mahmoud

# 6
I agree with suthan prabu. there is no formula to calculate.
depends on the manufacturers design, but full load curret can be calculated.

 Is This Answer Correct ? 16 Yes 9 No
Pillay

# 7
practically the no load current of 3 phase motor varies
from 25% to 35% whereas in 1phase it is nera to full laod.

 Is This Answer Correct ? 20 Yes 14 No
Surajkant

# 8
There is no standerd formula for calculating no load
current, It depend on the desine and material used in
motor. There is a major role of material(winding wire&
stamoing)to anhancing the efficiancy of motor.

 Is This Answer Correct ? 5 Yes 1 No
S.p.singh

# 9
3 ph induction motor will run 30% current on
no load but few motor will take 40% current

EXAMPLE:

KW=3.7KW,Amps=7.45,(Assume 40% Of No Load Amps)

= 2.98A

 Is This Answer Correct ? 4 Yes 0 No
K.arivazhagan

# 10
12A
 Is This Answer Correct ? 0 Yes 0 No
Maheshwar Das