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what are the procedure for testing the OLR relay ?
IN CASE of thermal Bymetalic Relay. Say Relay0.625-1 Ampere range, Set at1 Ampere. Apply3 phase load or current as1.2 Ampere-1.3 Ampere-1.5 Ampere.Relay Point95 &96 will take changeover from NC to NO , another Relay Point97 &98 will changeover from NO to NC.Generally relay was set considering130-140% Overload. If relay Point will not change then OLR is Faulty.In similar way we can check Overload relay of Higher Current. There are CT Operated OLR.for that also applying130% current of Set current,relay Overload Tripping Charecteristis to be checked.
There are Numeric/microprocessor OLR. For that by Secondary Current Injection( Full-Load current of MOTOR,TRAFO,Generator,All Electrical Accessories) in the CT Terminal for Set Current/Time.relay should be checked.
over load relay senses the excess current and trip the motor from overloading. apply2times,4times current through loading transformer. Normally if the relay not operated, Contact is in NC Position, If the relay get activated, then the contact get NO.
actually Fawaz Ahamed Mohamed Farook i didn't understood the question please say it with another format and i will try to answer you inshallah salllllllam
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