A P-N junction acts as a voltage-controlled switch. During forward biasied the p-n junction diode acts like an ON switch. When reverse biased, it acts like an OFF switch.
While estimating the overhead lines, the first and last pole is always earth connected and after every 3rd electrical pole, the fourth pole is earthed. Therefore, the approximate number of required ground set = 4
This type of motor is designed to operate with the start winding and it’s series capacitor permanently connected to the supply. lt has two capacitors connected in parallel in the start winding circuit for starting purposes. The running capacitor is employed to correct the power factor. As a result, this motor has a higher starting torque as well as a higher efficiency. These motors are employed in sizes ranging from 375 W to 7.5 kW. The power factor of these motor is upto 80% to 100%.
The factor by which, the induced E.M.F gets reduced due to short pitching is called pitch factor or coil span factor denoted by Kc. It is given as Kc = cosα/2 given α = 60° Kc = cos60/2 Kc = cos30° Kc = √3/2
EXAMIANS
