A circuit breaker and a fuse have a basic similarity in that they both______.A.can be reset to energize the circuitB.should open the circuit when overloadedC.will burn out when an over current flow developsD.should short the circuit when overloaded
A circuit breaker and a fuse have a basic similarity in that they both______.
A.can be reset to energize the circuit
B.should open the circuit when overloaded
C.will burn out when an over current flow develops
D.should short the circuit when overloaded
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A circuit breaker and a fuse have a basic similarity(类似) in that they both ______.A.can be reset to energize the circuitB.should open the circuit when overloadedC.will burn out when an over current flow developsD.should short the circuit when overloaded
A circuit breaker differs from a fuse in that a circuit breaker ______.A.melts and must be replacedB.is enclosed in a tube of insulating material with metal ferrules(环) at each endC.gives no visual indication of having opened the circuitD.trips to break the circuit and may be reset
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We have to ask ourselves if it is really as essential to a basic education as we______.A.resumeB.assumeC.summarizeD.consume
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单选题A circuit breaker and a fuse have a basic similarity in that they both （）.Acan be reset to energize the circuitBshould open the circuit when overloadedCwill burn out when an over current flow developsDAll of the above
单选题A circuit breaker differs from a fuse in that a circuit breaker （）.Amelts and must be replacedBis enclosed in a tube of insulating material with metal ferrules at each endCgives no visual indication of having opened the circuitDtrips to break the circuit and may be reset
单选题You are attempting to parallel two AC generators, and the syncope pointer is revolving in the fast directionThis indicates that the frequency of the incoming machine is （）.Ahigher than the bus frequencyBlower than the bus frequencyCthe same as the bus frequency but out of phase with itDthe same as the bus frequency and the circuit breaker may be closed at any pointer position
单选题Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine （）Aslightly less than the line frequencyBthe same as the line frequencyCslightly greater than the line frequencyDAll of the above
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