Mosquito lamp repair experience sharing

Update:15-06-2019
Summary:

First, the structure of electronic mosquito killer The […]

First, the structure of electronic mosquito killer
The Aikebo brand electronic mosquito killer lamp is a hanging and standing dual-purpose lamp. The outline structure is shown in Figure 1. It is mainly composed of UV fluorescent lamps, high voltage power grids, printed circuit boards, fences and casings. The 10w UV fluorescent lamp is installed vertically in the center of the high-voltage power grid, attracting mosquitoes and moths to fly. The high-voltage power grid is made of two sets of stainless steel wires with high-voltage electricity. It is installed vertically in the upper, middle and lower three grid positioning grids. The positive and negative poles are staggered and equidistantly arranged to form a closed high-voltage power grid. A transparent rod-shaped plastic fence is installed around the high-voltage power grid to allow mosquitoes to fly in and prevent the human body from touching the power grid. When the mosquitoes fly into the high-voltage grid and touch the electrodes, they are hit by high-voltage electricity and fall into the mosquito tray for easy cleaning.
Second, the working principle of mosquito killer circuit
The circuit of the mosquito killer lamp is shown in Figure 2, and the component wiring is shown in Figure 3. The umbrella circuit consists of a fluorescent lamp circuit and a two-voltage rectifier circuit.
1. Fluorescent lamp circuit This circuit is shown in the upper part of Figure 2. It is exactly the same as ordinary fluorescent lamp, except that the lamp emits ultraviolet light to induce mosquitoes to fly.
2. Double-voltage rectifier circuit This circuit is shown in the lower part of Figure 2. The power transformer is used to isolate the boost and it is safer to use. Close the power switch S, 220V mains is added to the primary circuit of the power transformer T2 via S, and the secondary of T2 is boosted to 420V. The current limiting resistors R1 and R2, the diodes VD1 and VD2, and the capacitors C1 and C2 form a double voltage rectifier circuit. When the T2 secondary AC power supply is positive half cycle, VD2 is turned off, VDl is turned on, and the charging voltage of C1 is the peak value of T2 secondary AC power supply voltage, that is, "root 2" × 420V. When the AC power supply is negative half cycle, VD1 is cut off, VD2 is turned on, the voltage on C1 is superimposed with the T2 secondary AC power supply voltage, and then charged to C2 via VD2. The charging voltage at both ends of C2 is the peak of T2 secondary AC power supply voltage. Times, the measured voltage on the road is 1250V. This DC high voltage is applied to both ends of the grid VE. When the mosquitoes fly over the fence and touch the high-voltage power grid, the VE two electrodes discharge the mosquitoes and kill the mosquitoes.