Compact non-contact refrigerator time delay protector circuit

Compact non-contact refrigerator time-delay protector This non-contact refrigerator protector has fewer components, low cost, small size, and no need for debugging. It uses a two-way thyristor instead of a relay. Working Principle The protector circuit is shown in Figure 1. The 220V AC power supply is stepped down by capacitor C1, half-wave rectified by VD1, and stabilized by VDW, and then supplied to the time base circuit 555 as the working power supply. After the power is turned on for about 5 minutes, the output terminal of pin ③ of the time base circuit changes from low level to high level. flat, the bidirectional thyristor VS conducts work and supplies power to the refrigerator. At this time, the light-emitting diode LED lights up, indicating that the power supply is normal.

See the attached table for component selection and production component selection. No. Name Model Quantity R1 Resistor 1M 1W 1 R2 Resistor 1K 1/8W 1 R3 Resistor 2M 1/8W 1 C1 Metallized paper capacitor 0.47u/400V 1 C2, C3 Electrolytic capacitor 100uF/16V 2 C4 Polyester capacitor 100n 1 VD1, VD2 rectifier diode IN4007 2 VDW Zener diode 2CW19 (12V) 1 LED light-emitting diode 1 VS triac 3A/400V 1 IC1 time base circuit NE555 1 This circuit uses fewer components and is easy to install. As long as the connections are correct, debugging is generally not required It will work normally.