Introduction
This circuit is used in large industries when the power is on
from the line and the three motors start after 10 seconds of time respectively.
In this circuit diagram, the circuit consists of three single phase motors each
motor is connected to the time relay switches. This circuit also consists of a
start / stop button, magnetic contactor and three overload relays which
protects the circuit from over voltage.
Circuit diagram
Explanation
When the start button is pressed then the magnetic contactor
energizes and the starting coil of motor 1 energizes and starts moving. After
10 seconds the time relay switch TR1 energizes and gives supply to the second
motor M2 and after 10 seconds the time relay switch TR2 energizes and provide
the supply to the third motor. TR1 and TR2 are on delay relay which cuts the
motor supply until the time relay switch is turn on.