How to measure whether the Zener diode leaks

Zener diodes are generally measured on an oscilloscope for leakage. A reverse voltage is gradually applied across the zener diode, and the leakage of the zener diode gradually increases when reaching the critical point. The higher the voltage, the greater the leakage current. Using a multimeter to measure the positive and reverse resistance of a zener diode can only roughly judge its good or bad.

We all know that zener diodes operate in a breakdown state, so we can use this characteristic to distinguish whether it is an ordinary diode or a zener diodee. Use a 500-volt micrometer, and the output end of the micrometer is connected in parallel with a multimeter. Either a digital meter or a pointer meter. Adjust the voltage range of the multimeter to 500 volts, shake the micrometer to deflect the needle in the forward direction. At this time, the red probe is positive.

Then lap the two probes on the two electrodes of the diodee under test. If you know the positive and negative poles of the diodee under test in advance, connect the red probe to the negative pole of the diodee under test and shake the meter. The voltage value measured on the meter is the stabilized voltage value of the stabilizer diodee. If you don't know the positive and negative poles of the diodee under test, shake it first to look at the voltage. If there is no voltage (0.5 volts), switch the probes before measuring. This method is suitable for detecting zener diodees below 200 volts. If the measured voltage exceeds 200 volts, the possibility of a diode is high, but it should be ruled out that this diodee is a low back voltage diode.