Brake Motor

Crane duty motors are specially designed for frequent starts/stops & reversing required in cranes & lifts of all types. They can also be used in applications such as material handling, weirs & sluices, auxiliary motors in rolling mills or wherever intermittent drives are required.
Range:
KW                       : 0.18 to 7.5 kW
Pole                     : 4P & 6P
Mounting              : B3, B5, B14 & combinations
Frame                  : 71 to 132
Voltage                : 415V ± 10% or as required
Frequency            : 50Hz ± 5% or as required
Ambient               : 50°C.
Altitude                : up to 1000m above msl
Rotor type            : Squirrel cage aluminium die cast
Enclosure             : Totally enclosed fan cooled (TEFC)
Protection            : IP44
Ins. class              : Class F with temp. rise limited to class B
Duty cycle            : S 1
Standards            : IS12615

Construction
Castings: Crane duty motors housings & end shields are made from high quality castings as per IS 210. All components are machined to correct accuracy & alignment.
Stampings: The stampings are made from low loss high permeability steel.
Terminal Box:  Standard location of terminal box is on top. However the terminal box on right or left side can be provided on request. The terminal box can be rotated in steps of 90° in each position.
Winding & Protection: All motors are wound with super enameled dual coat copper wires. This enable motors to be used for inverter applications as well. Features like vacuum pressure impregnation (VPI) & PTC thermisters embedded in stator winding can be provided on request.
Earthing terminals: Two earthing terminals are provided, one in the terminal box & other on the motor body.
Motors with integral brakes:
These motors can be supplied with integral electromagnetic DC fail safe brakes with built in rectifiers for frames up to  132.

Construction:

Brake Motors are used for various applications where instantaneous stopping of the driven load is required. The operation of the brake is “FAIL SAFE TYPE” i.e. normally ON. When the electrical power to the motor is cut–off or the power fails, the brake is applied.

Brake motor is a combination of an A.C. induction motor and an electromagnetic AC or DC brake. The electromagnetic brake is mounted on the non–driving end of the motor.

DC brake motors are provided with a rectifier which provides the required DC voltage to the brake coil which in turn operates the brake. The supply to the rectifier is fed from any two terminals (between any two phases) in the main terminal box of the motor.

General applications of Brake motors are printing machinery, textile machinery, rolling mills, cranes & hoists, material handling equipments, machine tools etc.

Working:

When the power to the motor is switched off, a braking torque is generated which presses the armature plate of the brake against the mounting flange. When the supply resumes, a magnetic field is produced in the brake coil and this pulls the armature plate against the spring force and the shaft is now free to rotate.