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
A circuit breaker differs from a fuse in that a circuit breaker ______.
A.melts and must be replaced
B.is enclosed in a tube of insulating material with metal ferrules(环) at each end
C.gives no visual indication of having opened the circuit
D.trips to break the circuit and may be reset
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Catalog sheets submitted with the bid must be “originals” and not copies; drawings, schematics and/or circuit diagrams and printed circuit board diagrams must be ().A、legislativeB、legionaryC、legibleD、legal
any pointer positionDue to failure of one of the carbon brushes the excitation voltage is lost on one alternator that operating in parallel.Then that alternator will() A.completely loose its share of the load causing the auxiliary engine to speed up.B.overload due to reduced voltage output and increased currentC.continue to share the active load(kw)but have high very reactive loadD.try to take all the load and so trip the main circuit breaker
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