It is a heavy duty, direct current, 4 poles and separately excited machine provided with interpoles.The motor with a fabricated magnet frame and rugged mounting feet is used for driving draw works, rotary and mud pump drives. Top mounted, 7.5 HP flame proof AC motor driven blower unit provides necessary cooling air to the main motor and also pressurizes its enclosures including the terminal box for making the drilling motor suitable for operation in hazardous areas. Since drilling motors do not have their own cooling arrangement that is why the top browser unit is provided for both cooling and removing spark occurring inside the machine. A 230 V AC, 225 Watts, single phase space heater is fitted in commutator chamber of each drilling motor for controlling the humidity when the machines are not working.