Zener diodes are normal PN junction diodes operating in a reverse biased condition. Working of the Zener diode is similar to a PN junction diode in forwarding biased condition, but the uniqueness lies in the fact that it can also conduct when it is connected in reverse bias above its threshold/breakdown voltage. These are among the basic types of diodes used frequently, apart from the normal diodes.
How to test Zener diode.
also, we can find the voltage on Zener diode
to find the voltage we need
1- DC voltage
2- 10KOhm resistor
3- Voltmeter
connect the battery to the terminal of the voltmeter and use resistor between them
this video Shows you how to find the voltage of Zene diode