One singlephase wattmeter plus miscellaneous apparatus as needed. The 3 phase set of currents, each of equal magnitude and with a phase. We thank you for making this choice, and would ask you to read the contents of this manual. Installation and maintenance threephase induction motors.
Find the starting current of 10 hp, three phase 220 v a class motor. 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. 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. 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. Conversion to mechanical power by motors pumps, fans, hvac, refrigeration compressors, power tools, food processors, escalators, elevators. Three phase ac induction motors are widely used in industrial and commercial applications. A 3 phase induction motor can be used for different applications with various speed and load requirements. Ac induction motors are also the most common motors used in main powered home appliances. These motors are selfstarting and use no capacitor, start winding, centrifugal switch or other starting device. Induction motor basics, single phase and three phase.
Record all nameplate information for the induction motor. The rotor will constantly be turning to align its magnetic field with that of the stator field. They have a good efficiency for a low cost and are very robust. Ac induction motors are also the most common motors used in main. These types of motors are known as selfstarting induction motors.
These are of two types, squirrel cage and slip ring motors. The three phase induction motors are simple in construction, rugged, low cost and easy to maintain. There are mainly two types of induction motor on the basis of power supply, single phase induction motor and three phase induction motor. The basic idea of an electric motor is to generate two magnetic fields. Output power shown by means of this resistance is zero. 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. Based on the rotor construction, 3 phase induction motor can be of two types. Ac introduction motors have been used in traction applications for a long time. Starting of 3 phase induction motors, high starting torque motors. Squirrel cage and wound rotor or slip rig induction motor. A three phase im, six poles, 50 hz is supplied by a three. An electrical motor is an electromechanical device which converts electrical energy into mechanical energy.
Example for this example, refer to the motor equivalent circuit and calculations described above. Applications of threephase induction motors of size varying from half a kilowatt to. A 12pole, 3phase alternator driven at a speed of 500 r. 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. One single phase wattmeter plus miscellaneous apparatus as needed. The threephase induction motor is the extensively used for various kinds of industrial drives. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. Cage induction machines institut fur elektrische energiewandlung. A 480v, 60 hz, 6pole, threephase, deltaconnected induction motor has the. You should also make a dc measurement of stator winding linetoline resistance.