The circuit diagram of the components used: 9,013 as shown in the figure is a better performance using the relay delay of light circuit. When you turn on the light, just press SB, lamp e power light. While, 220V Exchange electric by VS, and VD1, and C1, and C2, composition of capacitance buck half wave rectifier regulator circuit, in C2 ends output stability of 12V work voltage, transistor VT1 due to base very was following electrical touch points k-1 grounding and due, so VT2 guide pass, following electrical k was electric absorption close, touch points k-1 pour to often beginning, will press SB short circuit makes circuit since lock, so release SB Hou, lamp e still can power glow. At this point is the power to charge capacitor C3 by RP, R3, VT1 base potential gradually rising, when raised to a certain extent, VT1 breakover, VT2 due, that is made up of VT1 and VT2 Schmitt circuits turn back to their original state, the relay k release, contact k-1 reset, lamp e power supply circuits is cut off, the lights. Delay time circuit mainly by (RP+R3), charging time constant C3 decision, adjust the trimming resistor RP can set the delay time. C4 is through its charging current, can VT2 conduction instant relay k quick and reliable suction. Relay after the snap, because its line pack to maintain current is less than the current, as the R5 series of people, you can reduce the power consumption of relays to facilitate circuit work stable. K JZC-12F, DC12V miniature electromagnetic relay available, it has a set of conversion-contact, able to meet the needs of the circuit.