Three-phase motor energy consumption braking circuit (2)

As shown in the circuit in the figure, when braking, press the stop button STP, the AC contactor KMF (or KMR, KMF is a forward contactor, KMR is a reverse contactor, 1SA and 2SA are travel switches) lose power and release, and the motor M is disconnected from the AC power supply, the normally closed contact KMF or KMR returns to the closed state, the KM coil is powered and closed, and its three normally open main contacts are closed. The alternating current is added to the M stator winding through the KM main contact, and is passed through the rectifier diode VD1, VD2 is converted into direct current to enable the motor to brake quickly. At this time, the normally open auxiliary contact of KMF (or KMR) is disconnected, causing the time relay KT coil to lose power. After its delayed disconnection contact KT is disconnected, the KM coil is de-energized and released, and the KM main contact is disconnected. , cut off the braking DC power supply, and the braking process ends.