11KW Delta motor is taking about 44Amps in star and goes
upto 70Amps in delta and trips OFF. The rated current is
26Amps. Application is for the blower. The motor takes ( no
load without coupling impller ) only 2.5A and 5Amps in star
& delta starter test.Need to know why its taking high
current.

Answers were Sorted based on User's Feedback



11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / rajendran

The motor takes very less current at no load than the
normal and when it is loaded it is taking the obnormal
currents even in delta operating mode....

it seems there must be a problem in the connections or in
the supply voltage of the mains or improper impeller
arrangement causing very high load.

probably there may be a problem in the connections only...
check the connections

Is This Answer Correct ?    9 Yes 4 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / rajesh vallem

in blower applications before starting the motor damper
should be in close position.motor concerned it is ok
because no load current of the motor is ok.

Is This Answer Correct ?    5 Yes 0 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / gunasekaran

u r not explain proberly it is due to inrust current for
star phase voltage=VL/sqrt3
for delta phase voltage=line voltage so it is taking more
current than star.normally at stating motor taking 5to 6
six times of the full load current i think nothing wrong u
can incress the relay setting and then start the motor

Is This Answer Correct ?    2 Yes 1 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / boby

I think there is something wronng with imppller coupling
it alingment could be out. Because no load current of
motor is ok . So check the coupling alignment , motor
bearing and connection of input cable at main source.

Is This Answer Correct ?    1 Yes 1 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / mohammed raffi

In Blower application, starting current will be more than
normal until it gets full speed due to dampers, hence
better idea to use OLR with starting current delay time and
running current delay time setting. so that while starting
time this OLR waits for some time delay even starting
current is more than normal and trip.

Is This Answer Correct ?    0 Yes 0 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / tj

Following is the check seq. :

1 Check for correct DOR/Phase Seq, ensure termination is
correct n tight.
2 Check the relay for malfunction & its type if it is
thermal then increase setting a bit more than ratd amps &
chk, n if its micro proc based then adjust the setting
acording to motor starting curve.
3 Ensure that suction damper is at min. before starting.
4 Ensure the motor is correct according to fan torque.
5 Check for any abnormal sound or play from fan side.
6 Also check the cable, it should not be underrated, causing
higher potential drop at startup.

Hope the above helps you........

Is This Answer Correct ?    0 Yes 0 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / anil bhatia

check rated current as you mentioned 26 amps
according to chart it should be 19/20 amps

Is This Answer Correct ?    0 Yes 1 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / virendra

There could be two problems

1. the improper connection of the motor to starter mean the
phase sequence.

2. may be possible the one phase is missing & motor running
on 2 phasis means the single phasing phenomina

this is the only reason..........

Is This Answer Correct ?    1 Yes 3 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / felixraj

check the coupling alignment,blower condition(bearing)

Is This Answer Correct ?    1 Yes 5 No

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The r..

Answer / suraj_ojha

I am agree with mr.rajendern there is some mistake is in
their control wiring of starter.

Is This Answer Correct ?    0 Yes 5 No

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