With the help of neat diagram, explain operation of static relay.

With the help of neat diagram, explain operation of static relay.
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1 Answer

Answer :

Operation of Static Relay:

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Operation: 1) The solid-state component used are transistors, diodes, resistors, IC‟s, capacitor etc. The function of comparison and measurement are accomplished by static circuits. 2) Here the relaying quantity i.e. output of CT or PT or a transducer is rectified by rectifier. 3) The rectified output is supplied to a relay measuring unit comprising of comparators, level detectors, filters and logic circuits. 4) The output of relay measuring unit is amplified by the amplifier and fed to the output device which actuates the trip circuit as per requirement. 5) An auxiliary dc supply is provided for operation of static relay elements as shown in figure.

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