Close the circuit breaker QF in the power supply line and switch on the AC 220V power supply.
After the ac 220V voltage passes the rectifier and filter circuit, the output DC voltage supplies the time-base IC in the circuit, and the circuit enters the state of preparation.
As night approaches, the light intensity gradually decreases and the RG resistance of the photosensitive resistor increases.
As the resistance of photoresistor RG increases, the voltage drop increases and the voltage at the point A decreases.
When applied to the base IC IC, the 2 - and 6-pin voltage is changed to low level.
Time - based IC IC2,6 pins for low power, internal flip - flop, its 3 output high level, diode VD2 conducting.
After VD2 conduction, the thyristor VS conduction, the lighting street lamp forms the power supply circuit, and EL1~ELn is lit at the same time.
As the next day dawns, the intensity of the light increases and the resistance of the photoresistor RG decreases.
After the photoresistor RG voltage is divided, the voltage on the six pins increases gradually.
When IC2 pin voltage rises to more than 2/3VDD, 6 pin voltage is also greater than 2/3VDD, make IC internal trigger again
Second flip, IC3 pin output low level, DIODE VD2 cut off, thyristor VS stop.
Thyristor VS off, lighting lamp EL1 ~ ELn power supply circuit is cut off, all lighting lamps are off at the same time.