Experience in using zener diodes

We should pay attention to the following aspects when using zener diodees. The first is that reverse connection is needed in the circuit to stabilize the voltage. That is to say, the negative pole of the zener diodee is connected to the high potential in the circuit, and the positive pole is grounded. If the connection is reversed, the zener diodee will be burned due to excessive current. The second point is that the zener diode must stabilize when the power supply voltage is higher than its regulated value. Speaking of this, I remembered the maintenance of the health pot today. The fault of this circuit is due to the failure of the capacitor in the circuit. The input voltage of the zener diode is too low to only 2.7V. Because the regulated value of the zener diode 1N4733 is 5V, it cannot reach its regulated value, resulting in the inability to drive the microcontroller in the circuit board. This caused the entire circuit to fail to work properly. The third point is that if one regulator diodee cannot reach the regulated value, multiple regulators can be used in series, and remember not to use them in parallel.