ZC-2-10A 12v24v automatic charger circuit

Single-junction transistor BT33, C3, W1, W2 and other components form a relaxation oscillator. The pulse signal generated by it is sent to the control electrode of silicon controlled thyristor SCR1 through the isolation diode D4. Adjusting the resistance of W1 can change the trigger conduction of SCR1. Angle, that is, changing the charging current. Silicon controlled thyristor SCR2, relay J, W3, W4, D5 and other components form an automatic protection circuit when the battery is fully charged. When the voltage at both ends of the battery is charged to the upper limit set by W3 and W4, D5 is turned on and SCR2 is triggered. Pass, LED2 displays, the relay is closed, and J is switched to normally open at the same time, cutting off the control pulse concentration of SCR1, that is, stopping charging the battery. K2 is a switch for charging 12V and 24V batteries. The picture shows the switch in the 12V position.