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

inserting compensating winding

providing inter poles between the main pole

shifting the brush position from GNA to MNA

increasing the ampere - turns in the field winding

ebonite

mica

empire

glass

high carbon steel

cast steel

mild steel

wrought iron

mild steel

cast iron

copper

aluminium