Armature laminations are of high quality electrical grade steel. Commutator: Made from silver-copper-alloy. Electrolytic copper segments insulated from one another with mica. Riser connections are the TIG welded. Armature windings are impregnated with synthetic resin and properly baked at designed temp. to give complete protection against damage from moisture, acids and alkalies. Range: 0.25 HP to 20.0 HP Three phase supply and 0.10 HP to 1 HP Single Phase supply