1. Connect the+terminal of pointer multimeter (that is, the red stylus line segment, and the stylus polarity of digital multimeter is just opposite to that of pointer multimeter) to the-terminal of high-voltage diode, and connect the-terminal of multimeter (that is, the black stylus line terminal) to the+terminal of high-voltage diode. Measure the resistance with a multimeter R× 10K, and then connect the multimeter to two meters.

2. The measured resistance should be infinite, indicating that the high voltage diode is normal.

3. If the positive and negative resistance values measured by multimeter are infinite or small, the high voltage diode is damaged and needs to be replaced.

4. Measurement method: The primary coil of transformer is the most easily damaged place. The resistance of the primary coil to the ground can be measured with a multimeter. If there is resistance, it can be judged that the transformer is broken.

Extended data:

Matters needing attention in the use of microwave oven:

1, avoid heating ordinary plastic containers and plastic bags in the microwave oven: ordinary plastic containers and plastic bags are not resistant to high temperature and are easily deformed when heated. In addition, toxic substances may be released at high temperature, which is harmful to the body. You should try to choose a special container for microwave ovens with high temperature resistance.

2, avoid heating fried food: high temperature will spill oil, which may lead to open fire and fire. Do not open the door immediately if there is a fire in the furnace by accident. Turn off the power first, and then open the door when the fire goes out.

3. Avoid using metal utensils: The working principle of microwave oven is to use electromagnetic waves to heat food. Electromagnetic waves and metals will react, and there is no way to absorb or conduct them, and it is impossible to heat food in metal utensils.

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