DC motor reverse braking circuit b

 The circuit is shown in Figure 3-200 (a). When reverse braking occurs, the contacts of the forward contactor KMi are disconnected, the
contacts of the reverse braking contactor KM3 are disconnected, and the contacts of the reverse contactor KM2 are closed. The setting circuit of
    reverse-connected relay KA is shown in Figure 3-200 (h). Through the reverse connection relay KA, when the reverse connection braking starts
, the reverse connection braking resistor Rf is connected to the armature circuit; and when the motor speed is close to zero after braking, the reverse connection braking resistor
Rf is short-circuited. The connection point A of the relay KA coil is determined by the resistance value of R:. Point A should be
at half of the total resistance (Rq + Rf). The pull-in voltage of relay KA is generally set at (0. 4 ~ 0. 45) Ue.