A.Contactors control current and relays control voltage
B.A relay is series connected and a contactor is parallel connected
C.Contactors can handle heavier loads than relays
D.Contactors are made from silver and relays are made from copper
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A.short proof
B.ground proof
C.explosion proof
D.overload proof
A.prime mover speed
B.exciter output voltage
C.load on the alternator
D.number of poles
A.shunt field
B.circuit breaker
C.metal framework
D.inter-pole
A.brushes
B.slip rings
C.commutators
D.all of the above
A.is usual
B.is not usual
C.is necessary
D.is not impossible
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