Field resistance

Armature reaction

Inductive reactance

Armature resistance

Prevents heating

Reduces copper loss

Reduces windage loss

Prevents the hunting effect

50 rps

100 rps

1500 rps

3000 rps

Easy to locate the faults in the field

Easy to connect the load with alternator

Easy to dissipate the heat during running

Two slip rings only required irrespective of No. of phases

Prevents demagnetizing

Over voltage protection

Dead short circuit protection

Alternator will be over loaded