Chicken farm photoelectric control circuit

1) DC power circuit: 220V AC mains power through capacitor C. Step-down, diode VD2 half-wave rectification. VD3 stabilizes 9V and supplies the control
circuit.
    2) Light control circuit: The picture shows the working principle of this controller. In the picture, lcl and IC 2 use two new high-speed electronic switch integrated circuits.
When the voltage at the control terminal of IC1 is higher than 1.6V, it is turned on, otherwise it is turned off. The light control circuit sensor is acted by the photoresistor RG. When there is light
, the resistance becomes smaller and the light resistance is less than lOkfi. When the voltage drop drops to L 6V, IC1 does not conduct electricity, pin ② outputs low level, and the relay Kl does not Working
, bulb HI. not bright. When the day gets dark, the resistance of the photoresistor increases, and when its voltage drop rises to above 1.6V, IC1 is turned on, pin ② outputs a high
potential, relay Kl is closed, and the light shines, increasing the brightness of the chicken house. At the same time, The light-emitting diode LED1 emits light, indicating that the brightness is increased
. When the light becomes stronger, the relay Kl fork is released and the bulb HI. It also went out.
    3) Temperature control circuit: The temperature control circuit is composed of IC2 and other components. The thermistor RT used in the sensor has a negative temperature coefficient. When the temperature rises
, its resistance becomes smaller, the voltage drop of the thermistor is lower than 1.6V, IC2 does not conduct, the relay K2 does not work, and the heater has no power supply. When the temperature
drops, the resistance of the thermistor rises, and its voltage drop also rises. When it rises above 1.6V, IC2 is turned on, relay K2 is electrically activated, and
the working power supply of the heater EH is turned on, providing the chicken At the same time, I.ED2 lights up, indicating that it is in a heating state. When the temperature rises to a certain
value again, the IC 2 fork is cut off and the heater stops heating. This continuous cycle can ensure a constant temperature in the chicken house.
    (2) Component selection and production 1C1 and 1C2 use TWH8778 high-speed electronic integrated switch, VDS uses 2DW56 voltage regulator diode, and
RG uses photosensitive resistor with light resistance smaller than iokcr. RT selects a thermistor with a maximum change value of lOktl. Kl and K2 use JRC-21F type relay
t9V DC voltage relay. VD1~VD4 use 1N4001 diodes, and LED1 and LED2 use GaAsp type light-emitting diodes.
The control circuit board can also be purchased off-the-shelf. After welding and assembling according to the diagram, simple debugging can be carried out. However, the power circuit does not have a step-down transformer
, so the printed circuit board has 220V mains power, so be very careful when debugging.