单项选择题
A.series circuit B.grounded circuit C.short circuit D.closed circuit
If two AC generators are to be operated in parallel, th...
单项选择题If two AC generators are to be operated in parallel, the load is distributed evenly by（）
A.means of rheostat the governor settings B.a balance coil excitation C.adjusting the governor settings D.changing excitation
If a voltmeter is connected across a line, it must be p...
单项选择题If a voltmeter is connected across a line, it must be protected with a（）
A.shunt B.high-resistance coil in the armature circuit C.low-resistance coil in the armature circuit D.shunt and a coil of high resistance
When current and voltage reach maximum values at the sa...
单项选择题When current and voltage reach maximum values at the same time, the power factor is（）
A.minimum B.maximum C.leading D.lagging
