Outdoor lighting automatic control circuit schematic diagram

Turn on the power switch S. The 220V mains power passes through the fuse FU4 to the primary of the transformer T1. The secondary output of about 16V AC is added to the rectifier bridge UR for rectification. After rectification, it is stabilized by the voltage stabilizing integrated block IC 1 and filtered by the capacitors C1 and C2 to form a control circuit. Provide working power. IC2 and IC3 are NE555 integrated blocks. IC2 and peripheral components form a light control circuit, and IC3 and peripheral components form a timing circuit. When the light is strong during the day, the resistance of the photoresistor RG is small, and the reset terminal of IC24 pin is low level, the output of IC23 pin is the generation, the transistor VT1 is cut off, the relay K1 is disconnected, and its normally open contacts K1-1 and K1-2 are disconnected. , all bulbs are off.

Figure: Outdoor lighting automatic control circuit schematic diagram

When the light weakens, the resistance of the photoresistor RG gradually increases so that IC24 pin is high level, then IC23 pin outputs high level, VT1 is turned on, the breaker K1 is closed, the normally open contact K1-1 is closed, and KM1 When it is closed, the bulbs connected to the main contacts KM1-1, KM1-2, and KM1-3 light up. At the same time, the normally open contact K1-2 is closed, turning on the power of IC3, and its pins 4 and 2 are high level. IC33 pin outputs high level, transistor VT2 is turned on, relay K2 is drawn in, KM2 is drawn in, KM2-1, KM2-2, KM2-3 are connected to the bulbs controlled by the other part, and the lamps all light up. Since the relay K2 is closed, the normally closed contact K2-2 is disconnected, and the resistor R2 and the potentiometer RP1 charge the capacitor C4. When the voltage on capacitor C4 is charged to about 8V~9V, IC 3 is reset, pin 3 outputs low level, transistor VT2 is cut off, relay K2 is released, and normally open contact K2-1 disconnects the three sets of normally open main contacts of KM2 Of the controlled bulbs, only the bulb controlled by KM1 is on. Adjusting the potentiometer RP1 can change the lighting time of the bulb controlled by KM2.