Views:0 Author:Site Editor Publish Time: 2019-09-15 Origin:Site
The capacitor used in the microwave oven is not a common transformer capacitor, but a high-voltage transformer with "magnetic leakage" characteristics. The principle of "magnetic leakage" is used to achieve the purpose of automatically controlling the filament voltage of the microwave oven and the anode voltage. The influence of the phase lag of the leakage inductance voltage will reduce the utilization efficiency of the microwave oven, and the reactance characteristic of the high voltage capacitor is just opposite to the leakage voltage characteristic. The current phase leads the phase and has a good compensation effect on the leakage current of the phase lag. .
The reason why the high-voltage capacitor of the microwave oven has a big fire:
1) Due to poor maintenance, the magnetron output (waveguide) is seriously polluted. When the microwave oven is working, the oil is heated first, and the temperature is high to form a fire. Clean the furnace chamber, the volume output device and the vents, and clean and maintain them regularly, and the fire will be eliminated.
2) The double-voltage rectification high-voltage wire is too close to the chassis or the shell is touched. If the high-voltage wire is poorly insulated or encounters humid air, arcing occurs. Adjust the pressure-proof wire away from the chassis and insulate it with insulation if necessary.
3) Use the 500 type multimeter × 10K ohm resistance file, red and black bar to adjust the charge and discharge test, the resistance value changes between "infinity ∝ ~ 400K Ω", indicating that the capacitance is normal. If it is just a capacitor problem, of course, the thorough solution is to replace the high voltage capacitor.
The above is the cause of the phenomenon of sparking in the high-voltage capacitor of the microwave oven and the solution. I hope to help everyone.