First unplug the electrical power.
Using a 20,000 ohm, 2 watt resistor, this type of wiring component can be bought in most electronic supplies markets, and the price is very cheap.
Connect the probe of the resistor to the terminal of the capacitor to discharge the capacitor.
If the capacitor has three terminals, connect the resistor to one of the outer terminals and the middle terminal, and then connect with the remaining terminals and the middle terminal.
Connect one end of the resistor to a test lead and the other end to a crocodile clip, and wrap the discussion with insulating tape.
The crocodile clip is clamped on the ground wire. Use a test lead to connect the other pole of the capacitor. The discharge will not spark.
It is necessary to pay attention that if many capacitors are continuously discharged, the resistor will have a fever, you can choose a larger wattage.
The rest: (capacitor)
Lamp tube discharge, method two is similar to 100-200 watt lamp tube.
Discharge with a 60-80W soldering iron, the method is similar.
Discharge from the ground.
Non-professionals should not take the test without permission.