单项选择题

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 at each end
C.gives no visual indication of having opened the circuit
D.trips to break the circuit and may be reset

点击查看答案&解析

上一题目录下一题

相关考题

单项选择题

Voltage generated by most AC generators is fed from the machine to the bus by means of（）.

A.brushes on a commutator
B.brushes on slip rings
C.slip rings on a commutator
D.direct connections from the stator

单项选择题

Electrical leads and insulation on a motor should be painted with（）.

A.heat-resisting acrylic
B.heat-resisting aluminum
C.insulating varnish
D.insulating white lead

单项选择题

The electrolyte in a lead-acid storage battery consists of distilled water and （）.

A.hydrogen chloride
B.calcium chloride
C.sulfuric acid
D.muriatic acid