2 slip rings
3 slip rings
4 slip rings
6 slip rings
phase sequence meter
synchroscope
power factor meter
tachometer
indicate the correct instant of synchronizing two alternators
connect the incoming alternator to the bus bar
adjust the frequency of incoming alternator
indicate the correct phase sequence of the incoming alternator and bus bar
increase the eddy current losses
reduce the eddy current losses
increase the magnetic flux
decrease the speed of the rotor