HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER FEEDER AT START AND RUN

HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER
FEEDER AT START AND RUNNING?

Question Posted / karani

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HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER FEEDER AT START AND RUNNING?..

Answer / fairos

First, for thermal overload relay has no meaning in term of setting it while on running or starting. It purely based on rated current of the motor.

when you look at the nameplate of the motor there should be a data that mention "duty" which normally either 1, 1.1 or 1.2 in value. If the duty is 1 then you can only set the overload relay at 100% of the rated current. If duty is 1.1 then the motor is allowed to operated at 10% higher than it rated current hence you can set your relay at 110% of rated.

Generally people would set at 10-15% higher than rated current. But sometimes being conservative is okay, which you can set the relay below the rated current. This can be done as long as it is not tripping unnecessarily.

Is This Answer Correct ?

22 Yes

3 No

HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER FEEDER AT START AND RUNNING?..

Answer / vilas

First take a current of each phase with tong tester,while
running on normal load,
Then set the over load accordding to the load slightly
higer than normal running current, care should be taken
that it should not be more than rated current which is
always mentioned on the motor name-plate.

Is This Answer Correct ?

7 Yes

7 No

HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER FEEDER AT START AND RUNNING?..

Answer / pankaj sharma

Set the relay to motor full load current as mention on motor plate

Is This Answer Correct ?

5 Yes

5 No

HAI,HOW TO SET THERMAL OVERLOAD RELAY FOR DOL STATRTER FEEDER AT START AND RUNNING?..

Answer / mohit

set thermal overal relay to 95% of full load current of
motor.