How to measure the quality of a diode or triode with a digital universal meter

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The digital meter has a file that measures the circuit (or line) on and off, and there is a beep sound if it is not, and it is silent if it is not passed. Using this sound, you can measure the quality of the diode or triode: measure the diode forward and negative twice, and one of them has a sound (that is, when the diode is connected in the forward direction, the diode is on, and there is a beeping sound), which is good; Otherwise it's bad.

The triode is measured with 1k or 10k gear, and the positive and negative measurements between the two poles are measured twice, which is in line with the on-off principle of the diode, which is good, otherwise it is bad.

The specific operation method of measuring diodes with a digital universal meter is as follows:

1.First, the multimeter selects the diode gear.

<>3.If there is no reading, the pen will be reversed and measured again; If there is no indication for both measurements, the LED is damaged.

4.Zener diode: The end with a black ring is negative. When using the meter, if there is an indication, the end measured by the red pen is positive, and the end of the black pen is negative.

5.If not, test again. If there is no indication for both measurements, the Zener diode is damaged.

6.Rectifier diode: The one with the white circle is negative. When using the meter, if there is an indication, the end measured by the red pen is positive, and the end of the black pen is negative.

7.If not, test again. If there is no indication for both measurements, the rectifier diode is damaged.

Here's how to measure the quality of a diode with a multimeter:

1. Hit the file to the diode file, insert the red watch pen into the V hole, insert the black watch pen into the com hole, and the red watch pen is positive and the black watch pen is negative.

2. If there is no number in the reverse connection, it is good if there is a number in the positive connection, and if there is no number display in the reverse connection, it is bad.

3. If the reverse light-emitting diode does not display the number and does not emit light, and the positive connection has a few weak light, it is good. In the same way, the reverse is bad.

Extended Content:

Diode. <>

1. Introduction. A diode, a device with two electrodes that allows current to flow in a single direction, is used in many electronic components to apply its rectification function.

Varactor diodes (VAFIC diodes) are used as electronic tunable capacitors. The current directivity of most diodes is often referred to as "rectifying". The most common function of a diode is to allow only current to pass through a single direction (known as forward bias) and to block it in reverse direction (known as reverse bias).

Therefore, the diode can be thought of as an electronic version of the check valve.

Encyclopedia diodes.

The multimeter has a special diode measurement file, dial the multimeter dial to the diode file, when the red watch pen is connected to the positive pole and the black watch pen is connected to the negative pole, the multimeter reading is generally left and right, and when the reverse is connected (the red watch pen is connected to the negative pole, the black table pen is connected to the positive pole), the multimeter reading is 0L, if the multimeter measures that the diode is read forward and backward is or 0L, it means that the diode has been damaged.

Put the multimeter in the R 100 or R 1K gear, connect the two meter pens to the two electrodes of the diode respectively, measure one result, then switch the two meter pens, and then measure the other result. In the results of the two measurements, one of the measurements has a large resistance (reverse resistance) and the other has a small resistance (forward resistance). In a measurement with a small resistance, the black pen is connected to the positive pole of the diode, and the red pen is connected to the negative pole of the diode.

Precautions for the use of multimeters.

When it is not clear the size of the voltage or current value to be measured, the highest gear should be used first, and then the appropriate gear should be selected according to the measurement results, so as to avoid the watch hand deflecting too much and bending the watch hand or damaging the watch head. However, the closer the gear is to the measured value, the more accurate the measured value will be.

When measuring DC voltage and DC current, pay attention to the positive and negative poles, and do not connect them incorrectly. If you find that the watch hand is reversed, you should immediately replace the watch pen to avoid damage to the watch hand and watch head.

The above content refers to Encyclopedia-Multimeter.

Encyclopedia diodes.

Measure the quality of the diodeFirst of all, you need to know its model, function, and then check the manualAccording to the parameters provided in the manual, the results detected by using the multimeter can be checked against whether the parameters of the manual meet the requirements. There are many varieties of diodes, with different functions and different measurement methods. It's hard to go one by one.

If you only measure ordinary rectifier diodes, it is generally sufficient to measure the forward and reverse resistance. If you measure the voltage regulator tube: first check the forward and reverse resistance, and then apply a variable voltage (to give the working current), and measure whether the primary breakdown voltage value meets the data given in the manual, if it deviates seriously, it cannot be used.

For example, to measure a bidirectional diode, it is also necessary to connect a measurement circuit, and two multimeters are needed to monitor the voltage and current at the same time. ......The diode detection method is different for different functions.