Electrical appliances are an integral part of home life. Each apartment and private house has several pieces of equipment that perform a wide variety of functions. Some are designed for cooling, while others are for heating and constant maintenance of high temperature. About the last type of devices and it will go.
Microwave ovens are firmly entrenched in everyday life and have become reliable helpers in the kitchen. They are simple in design and may include various options. But, despite its reliability, the product of each manufacturer may begin to function incorrectly. Errors appear and, ultimately, the microwave stops working. One of the most common problems is considered to be a malfunction of a high voltage diode. Therefore, it must be checked first.
Device device
Whatever the cost of the furnace, in any case, the moment will come when it will not turn on. And so, how to avoid breakage fails, you should learn how to diagnose the device. Signs of a microwave failure will not always be apparent. Quite often, a product simply stops heating products without any sparks and smoke. If this is the situation, it’s very likely to fix the stove yourself. Check that all components are in good condition.
Components:
- Capacitor;
- High voltage diode;
- High voltage transformer;
- Fan cooling elements;
- Magnetron;
- Temperature fuse;
- Bowl rotating motor;
- Filter;
- Circuit breakers.
Breakdown reasons
All microwave ovens operate properly for a sufficiently long period of time. This is primarily due to the high reliability of components. But over time, some of them fail, despite the neat operation of the equipment. Therefore, you need to check all the components. The most common malfunctions of the following parts:
- High voltage fuse;
- Capacitor;
- Transformer breakdown;
- Rectifier diode.
Each of these malfunctions can be eliminated independently. As a rule, in case of problems with the operation of the device, owners of microwave ovens have to deal with a diode.
Important detail
High-quality repair of the product as well as its diagnostics can be carried out only if the composition of the diode is understood.
At its core, a high-voltage type product is a combination of a large number of simple rectifier diodes. All of them are predominantly identical, and together make up one housing. The assembly of each such product does not imply the use of a variety of resistors and capacitors, which are designed to equalize the voltage. The current-voltage characteristic of the diode is non-linear. In this case, the resistance of the product depends on the voltage that is applied during operation.
It is worth emphasizing that verification accurate verification of the part is impossible if you use a conventional tester. The device simply does not show accurate data. With its help it is impossible to establish the correct forward and reverse resistance. To obtain more accurate indicators, it will be more efficient to use a high-quality multimeter.
To check the diodes, you must switch the multimeter to the range "R x 1000". When the positive terminal of the device is connected to the anode of the high-voltage diode, a resistance test is performed. An ordinary tester in this case will not be able to determine objective indicators.
The next type of test involves connecting a negative contact. In this case, the indicator is checked in the opposite direction. Its value must correspond to infinity.
Methods for assessing the condition
As practice shows, the high-voltage element must be turned over in order to check the resistance in both directions.
The process of detecting a malfunction in the operation of the diode occurs in certain stages:
- Initially, it is required to disconnect the microwave oven from the network;
- After this, it is necessary to disconnect the high-voltage diode from the electrical circuit;
- At the end, you need to connect the element to the lighting. As a kind of sensor, they take an ordinary bulb of only 15 watts.
Most often, an incandescent lamp shines only half of its rated power. At the same time, its flicker is observed.
Many experts also use a different verification method. It also involves the use of a light bulb. Only this time should take a 20 watt lamp. The processes are identical in principle:
- Connection of the tested diode to the bulb;
- Evaluation of the health of an element with diodes connected in one direction - the lamp gives out half of its power;
- Flip diode.
If the glow noticeably changes, this means only one thing - it turned out to ring the diode and, unfortunately, it is broken. Therefore, urgent replacement is required.
But the methods do not end there. There is another, very effective approach. This will require very few improvised means - the charger is either from a smartphone or from a tablet. The presence of a multimeter “Tseshki” is a must!
When conducting the test, it must be remembered that charging from mobile phones and similar devices, as a rule, give out a voltage of 5 V.
Operating procedure:
- We remove the high-voltage diode from the microwave network;
- We connect the element to the multimeter;
- Set the measuring device to 10 V.
As a result of such a measurement, the device should show a value of 0.25 V. This will mean that the diode is completely intact and its replacement will not be required. An interesting observation is that the measurement in the opposite direction will not give any indicators.
How can this method determine that the product is defective? It's simple - a broken part will not show any data, either in the forward or backward direction. It is also worth emphasizing that a product requiring replacement will not in any way affect the light bulb. It will either shine evenly all the time, or it will not light up at all.
In this situation, it is possible to diagnose a voltage drop. And sometimes even its complete absence. If the test showed just such a result, immediately change the diode. He will not work. Make the microwave function as before a breakdown can only a new high-voltage product.
Replacement should take into account one important rule - the conclusions of the diodes are completely different. In this case, the differences apply both to the purpose and the connection method. The positive contact of the product, which is called the "anode", has a ring at the end. It is made specifically for fastening with a bolt. The end must be marked. Negative contact "cathode", has a bracket at the end. It is connected to a capacitor.
Using the above methods will help to establish problems in the operation of the high-voltage diode and to carry out its quick replacement.Use accurate multimeters, quality parts and the microwave will work for many years.