Video: Watch this demo
Description: This demo shows what happens when you short a large capacitor.
- High voltage DC power supply
- Industrial strength 100microfarad 800VDC capacitor
- Large screwdriver
- Two wires
- Disconnect the shorted wire from the capacitor.
- Connect the cables to the capacitor.
- Adjust the power supply to about 400VDC.
- When the professor is done, discharge the capacitor again and connect a wire to short the terminals.
- Turn on the power supply and let it charge for about 30 seconds.
- Turn the power supply to standby.
- Touch the screwdriver to both terminals of the capacitor and watch the large spark. Make sure you are holding the insulated part of the screwdriver.
- When finished, turn the power supply off and discharge the capacitor for safety.
Concept: This demo is simply used to illustrate how you can quickly discharge a capacitor. To “short” a capacitor means to place a conductor directly from one terminal to another to allow the capacitor to quickly discharge rather than to do so slowly, causing a spark.
High Voltage / High Current
This capacitor can hold a lethal charge!
Never touch the terminals.
Always discharge the capacitor after use. Attach a cable connecting both terminals when putting away for safety.