Motor Y-△ starting circuit

Working principle of the circuit: Press the start control Q, 1JC is powered on, and the motor
stator winding is connected into a Y-shaped connection. At the same time, connectors 1 - 15 are connected, 2JC is powered on, and the
motor Y-shaped connection is decompressed and started. When 1 - 15 is turned on, JMP-S is also powered to work, and
the motor speed is detected. When the motor speed reaches 60% to
80% of the rated speed (can be set according to the actual situation), JMP, pull-in, 1- 7 is disconnected, IJc is de-energized
and released, the Y-shaped connection is disconnected, 1-9 are connected, 9-11-13 are also connected, 3JC is powered on
and the stator winding of the motor is connected into a △ shape, entering full voltage normal operation , the Y-△ shape
is automatically started. JMP-S is still powered on and continuously
monitors the operation of the motor. When the motor's speed drops by 10%~20% due to external reasons such as overload, phase failure, excessive power supply voltage
drop and other unexpected situations, JMP2 is disconnected, 2JC and 3JC
lose power and are released successively, and the motor power is cut off to protect the motor from Damaged due to overload, phase failure
, or low power supply voltage . At the same time, JMP-S also loses power, and JMP, and
JMPi return to their original status in preparation for restarting.