Book at a Glance

PART I - Electric Motors, Drives and Energy Saving

Chapter 7. Special-purpose Motors and Induction Generators

Textile motors
Crane motors
Determining the size of motor
Sugar centrifuge motors
Motors for deepwell pumps
Motors for agricultural application
Surface-cooled motors
Torque motors or actuator motors
Vibration and noise level
Service factor
Motors for hazardous locations
Specification of motors for Zone 0 locations
Specification of motors for Zone 1 locations
Motors for Zone 2 locations
Motors for mines, collieries and quarries
Intrinsically safe circuits, type Ex. ‘i’
Testing and certifying authorities
Additional requirements for critical installations
Motors for thermal power station auxiliaries
Selection of a special-purpose motors
Induction generators

Selection of special-purpose motors Checking the suitability of a slip-ring motor
With the same pull-out torque as above, if we select a slip-ring motor and arrange the starter to develop an average pick-up torque of 200%, the available accelerating torque will be (200 – 68) = 132%. To determine the number of equally spread starts and stops, heating and cooling curves of the motor should be available and the manufacturer may be consulted. The above exercise is only for a general guidance. In such cases, the manufacturer should be consulted who may offer a better and more economical design.

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