These types of motors are known as selfstarting induction motors. Induction motor basics, single phase and three phase. They have a good efficiency for a low cost and are very robust. You should also make a dc measurement of stator winding linetoline resistance. Ac induction motors are also the most common motors used in main. A 480v, 60 hz, 6pole, threephase, deltaconnected induction motor has the. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. The basic idea of an electric motor is to generate two magnetic fields.
Output power shown by means of this resistance is zero. The threephase induction motor is the extensively used for various kinds of industrial drives. A 3 phase, y connected, 460 volt line to line, 25 horsepower, 60 hz, 8 pole induction motor has the following constants, in ohms per phase referred to the stator. A 12pole, 3phase alternator driven at a speed of 500 r. In this case, power flows from the mechanical system, to the rotor circuit, then across the air gap to the stator circuit and external electrical system. A three phase im, six poles, 50 hz is supplied by a three. Based on the rotor construction, 3 phase induction motor can be of two types. Starting of 3 phase induction motors, high starting torque motors. Squirrel cage and wound rotor or slip rig induction motor.
Conversion to mechanical power by motors pumps, fans, hvac, refrigeration compressors, power tools, food processors, escalators, elevators. In the case of three phase ac alternating current operation, the most widely used motor is a 3 phase induction motor, as this type of motor does not require an additional starting device. Cage induction machines institut fur elektrische energiewandlung. We thank you for making this choice, and would ask you to read the contents of this manual. Installation and maintenance threephase induction motors. Three phase induction motors master line 3 mounting characteristics powers up to 50,000 kw voltages from 220 to,800 v speed from 3,600 to 300 rpm manufactured in different configurations of cooling methods and degrees of protection, adapting to the operating and environmental conditions. Ac introduction motors have been used in traction applications for a long time. These motors are selfstarting and use no capacitor, start winding, centrifugal switch or other starting device. A 3 phase induction motor can be used for different applications with various speed and load requirements. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. The 3 phase set of currents, each of equal magnitude and with a phase.
One single phase wattmeter plus miscellaneous apparatus as needed. Three phase ac induction motors are widely used in industrial and commercial applications. There are mainly two types of induction motor on the basis of power supply, single phase induction motor and three phase induction motor. Example for this example, refer to the motor equivalent circuit and calculations described above. Record all nameplate information for the induction motor. An electrical motor is an electromechanical device which converts electrical energy into mechanical energy. Code factor is a number which is reserved for class for example, all motors of class a have a fixed code factor which should be multiplied with rated hp in the above equation.
Find the starting current of 10 hp, three phase 220 v a class motor. The rotor will constantly be turning to align its magnetic field with that of the stator field. Ac induction motors are also the most common motors used in main powered home appliances. These are of two types, squirrel cage and slip ring motors.
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