A.minimumB.maximumC.leadingD.laggingWhen current and vo……

单项选择题Which is an acceptable means of correcting high mica between commutator bars?（）

单项选择题Generator brushes are staggered to（）

A.reduce current pulsations
B.reduce brush chatter
C.prevent uneven commutator wear
D.allow greater power generation

单项选择题The voltage output of an AC generator is controlled by（）

A.varying the DC exciter voltage
B.varying the reluctance of the air gap
C.regulating the speed of the prime mover
D.shorting out part of the armature windings

单项选择题If two AC generators are operated in parallel, the load is distributed evenly by（）

A.a rheostat
B.a balancing coil
C.changing field excitation
D.adjusting the governor settings

单项选择题What would the amps be at 240 volts with an 8 ohm resistance?（）

A.32~5 amps
B.25 amps
C.1~5 amps
D.30 amps