SUBJECT industial electricity Following is a three phase mo

SUBJECT : industial electricity

Following is a three phase motor control circuit with reduced-voltage staring. RT is a time delay relay in the circuit. Explain in detail what happens after the start button is push till the motor reaches full speed. Explain what happens after the stop button is pushed till the motor stops. Where is the purpose of using the three resistors in the circuit?

Solution

(a) ans

if we push the starts botton that we close the circuit and we allow to current(or) electrical energy to passes through the system

the current (or) electrical energy is convert to heat energy

later heat energy is converted to mechanical energy

so the motor reachs to complete speed to do the work

(b) ans

if we push the stop bottom the key of the circuit is open then current (or) electrical energy passing is stop so the mechanical energy is converted is electrical energy

(c) ans

the purpose of three resistance is used in the circuit to reduced the high voltage current