How to check the high voltage diode in the microwave

Microwaves have long appeared in homes for convenient heating of food. They are quite simple to manage and affordable.

Despite its reliability, the product is not protected from inevitable technical failures. At some point, it just stops working. The main reason is the failure of the high voltage diode.

A high-voltage diode is a few parts connected in series with each other in a common housing. The package includes a special rectifying diode. This product is endowed with a non-linear current-voltage specification.

Such a microwave detail can not be measured with a conventional tester, you need to use a multimeter.

Diode test

Important. For the procedure, the oven must be disconnected from the power supply. The cord is removed from the outlet.

Then produce a visual inspection of the microwave. If there are no melted spots, darkened areas, it is necessary to use a special measuring device.

How to find a high voltage diode

The mechanism works according to one principle. But there are many varieties of this element. The design of the microwave oven has a board with a marking. The desired item is usually indicated by DB 1.

Once you figure out which model your microwave belongs to, you can replace the part with a similar element. The marking will be different, but the type of operation of the product is the same. Each manufacturer simply has its own marking system.

The technical characteristics of the part are as follows:

• current output up to 700 mA;
• the highest voltage is about 5 kV.

How to check a high voltage diode with a multimeter

To assess the condition of an important part, you need to use a special device - a multimeter.

After disconnecting the heating equipment from the power supply and taking out the furnace element, it is necessary to turn the part over. This will measure voltage from two sides.

Resistance is measured in both forward and reverse directions.

• The multimeter must be turned on in the R x 1000 mode.
• Connect it to the diode, to the terminal with the + sign (this is a direct resistance). The tester should show the final resistance on the screen.
• After that, connect to the output with a minus sign. This is a measurement of the reverse direction of resistance. The tester should display infinity.

Important. Connect the multimeter to the network at least 9 volts.

Checking the high voltage capacitor with a multimeter is possible only for a breakdown. If the device shows a short circuit, the part must be replaced.

Indicators of the state of the high-voltage diode

An ordinary tester, as we figured out here, will not work. Since the highest limit of resistance measurement is 2MΩ, such a device will always show in this case an “open” circuit.

If you decide to take the measurement yourself, you need to know how it works correctly.

• If the item is in good working order, the pointer of the multimer will show 0.25 volts. EIf you check the resistance in the opposite direction, then it will not show anything.
• The failure of the part is indicated by the lack of indicators when measuring in all directions. In the event of a breakdown, the mechanism lamp will glow steadily or not at all.

Given the above data, we can conclude that the high-voltage diode in the microwave is defective and must be replaced with a new element. After replacing the microwave element, the oven will function as new.

When checking the resistance on both sides, it is important to know: the findings differ in purpose and connection.

The element of the mechanism with the + sign is marked on it and ends with a bolt at the end - this is the anode.

The output with a sign - there is a connection to the capacitor, and it ends with a bracket - this is the cathode.

If the microwave strip is not in a malfunction of the high-voltage diode, it will be difficult to repair and check it yourself.