Thermal overload relays are used to protect the motor against over current due to____________?

Related Mcqs:

Which of the following medium is employed for extinction of arc in air circuit breaker?

A. Water B. Oil C. Air D. SF6...

The arc voltage produced in A.C. circuit breaker is always_____________?

A. in phase with the arc current B. lagging the arc current by 90″ C. leading the arc current by 90° D. none of the above...

Interruption of large currents by relay requires______________?

A. arc suppressing blow out coils B. wide separation of the opened contacts C. high speed opening of contacts D. all of the above...

For which of the following ratings of the transformer differential protection is recommended ?

A. above 30 kVA. B. equal to and above 5 MVA C. equal to and above 25 MVA D. none of the above...

A balanced 3-phase system consists of_______________?

A. zero sequence currents only B. positive sequence currents only C. negative and zero sequence currents D. zero, negative and positive sequence currents...