4

6

8

12

In series with armature

In parallel with armature

In series with shunt field

In parallel with shunt field

Build up the voltage

Reduce the field current

Reduce armature current

Maintain constant output voltage

Resistance between the opposite brushes

Resistance between brush and commutator raiser

Resistance between brush and commutator

Resistance between brush and armature conductors

Long shunt compound

Cumulative compound

Differential compound

Short shunt compound