HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in d

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HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL
STARTER?
& in dol why it is require circuit breaker?

Question Posted / ram

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HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / x man

for OLR---It has to be Motor full oad current
for Contactor--it has to be 1.5 timmes the motor rated
current.
Circui breaker is used to protect the circuit.
for A tYPR 2 cordination these three componenrs are needed
in the circuits

Is This Answer Correct ?

13 Yes

6 No

HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / ermias solomon

in OLrelay 115%*motor name plate current
for contactor use
NEMA table by ermias solomon

Is This Answer Correct ?

1 Yes

1 No

HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / christopher pino

Refer to NFPA 70 - NEC 2005 (Article: Motor Protection) for
sizing and other consideration.

Is This Answer Correct ?

1 Yes

3 No

HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / barkha

In case of DOL Starter overload relay range depend on full
load current(flc) of the motor it is 2-3 times of flc &
also keep in mind the fuse rating of the motor

Is This Answer Correct ?

11 Yes

15 No

HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / nikhil chugh

THE CONTACTOR RATING SHOULD BE 3.5 TIMES GREATER THEN THE
MOTOR CURRENT RATING FOR SMOOTH RUNNING OF THE MOTOR WITH
PANEL

Is This Answer Correct ?

1 Yes

5 No

HOW DO I CALCULATE OVER LOAD RELAY & CONTACTOR IN DOL STARTER? & in dol why it is require..

Answer / k.suresh

motor full load ampes & 6 time higher select OLR AND
Contactor.