What is the difference between an auto reset and manual reset overload relay?

What is the difference between an auto reset and manual reset overload relay?
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1 Answer

Answer :

a. Auto reset relay closes its contacts when the bimetallic strip gets cooled. In manual reset relay we have to manually reset the relay because even though bimetallic strip cools its contacts are not closing without manual reset. L & T type OLR have only manual reset and siemens type has both manual and auto facility. 

b. Auto reset over load relay is reset by switching OFF the respective had switch and again switching it ON. 

c. Manual over load relay is reseted by pushing the reset button provided on the MCC cell. 
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Related questions

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Last Answer : Answer: C

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