brass

hard drawn copper

bronze

steel

convert AC into uni-directional current

collect the current from the commutator

increase the magnetic flux

connect the armature and commutator

poles

armature coils

parallel path

brushes

increase the flux around the conductor

decrease the flux around the conductor

rotate the magnetic field over the conductor

set the pole and armature to touch each other

The armature core is not properly laminated

The generator is kept idle for a long time

The armature resistance is more than 1 ohm

Incorrect brush position