These rugged & reliable ranges of DC motors are manufactured in Ahmednagar.

The plant has the facility to manufacture the 810, 818, 816, 814, 812, 808, 806, 804, 803 and 802 frames. Laminated Yoke motor frames 100 to 630 are also manufactured at this facility.

Constructional Features ( 315 to 630 frames)

Armature: Armature core is built of 0.5 mm thick loss cold rolled electrical grade steel stampings. It is provided with adequate axial holes in the stampings for effective ventilation. The armature shaft is made of high quality steel forging. The core is shrunk on the shaft. The armature coils are made from high thermal grade dual coated rectangular enameled copper conductors of 210 deg. C class. The completely wound armature is VPI treated in class H solvent less polyesteramide resin. The armature is dynamically balanced to a high degree of precision.

Commutator: The commutator is made of high conductivity hard drawn copper segments of trapezoidal profile. The segments are insulated from each other by epoxy mica class "f" spacers having high compressibility which provides dynamic stability at all speeds. Commutators are specially designed with glass fiber taper rings in place of conventional V-Rings, to make them suitable for high-speed applications.

Magnet Frame: The magnet frame is designed with octagonal shaped laminated yoke construction for four pole machines and polygonal for six pole machines. The laminated yoke construction ensures capability to withstand high DI/DT of the order of 250 In per second. The main pole and interpole cores are built with CRCA steel laminations.

Insulation: The shunt field, interpole and compensated coils are made from high thermal grid dual coated round/ rectangular enameled copper conductors of 210 deg. C class. Shunt field coils are wet wound with epoxy resin system which, after curing , becomes a solid mass. The completely wound stator is impregnated in class H solventless polyesterimide resin followed by deep impregnation in polyesterimide varnish to make it dust and moisture proof.

Brush gear: This is of robust construction and constant force spring brush holders are used to ensure constant pressure throughout the life of the brush. This gives excellent commutation performance and longer brush life. Proven grades of electrographite brushes are used to give satisfactory commutation. Adequate openings are provided in the end shield/cover for maintenance of brush gear.

Testing: Motors are finally type tested thoroughly on three phase, six pulse thyristor supplied to ensure the performance.

Optional Accessories: Temperature detectors in bearings and stator windings, space heaters in tachomounting provision, air flow switches, water leakage detectors, pressure switches, filters, over speed devices, break mounting provision, etc.