Single phase motors Essay Example | Topics and Well Written Essays - 500 words

Single phase motors - Essay Example It is also called an induction start and induction run motor. This is the simplest from of a single-phase motor meant for small industries. There are two windings. While the starter winding has fewer gauge wiring and turns, the main winding has higher gauge wire with more turns. This puts the start winding field ata different angle to the main winding field, resulting in the motor to rotate. Then the main winding, which is of heavier wire, takes over and keeps the motor running. When the speed reaches up to around 75% of its peak , the switching mechanism, mainly a centrifugal switch on the motor shaft, disconnects the start winding from the main one. Although the application of such motor is advisable only for those jobs where the staring torque requirement is not high, this type of motor is least expensive for industrial uses. This type is the most widely used motor for industrial applications. While this is similar to the split phase motor, the starter winding has a capacitor in the circuit, which gives a boost to the starting function. Here again the start winding and the capacitor are disconnected when the motor reaches up to 75% of its rated speed. Due to the wider applications, including those where the starting torque requirement is high, this type of motor is more expensive than the split phase type. These motors can be used for most of the belt drive applications like, small conveyors, Blowers and pumps. These can also be used for both, direct drive as well as geared applications This type of motor neither has the capacitor connected to the start winding nor a switch for disconnection. However, a capacitor is connected to the start winding permanently, in series with it. Once the motor reaches its running speed, this run type capacitor turns the start winding into an auxiliary winding. The starting boost is missing