Capacitor Energy Storage Equipment Safety

Are capacitors a hazard?

Another hazard exists when a capacitor is subjected to high currents that may cause heating and explosion. Capacitors may be used to store large amounts of energy. An internal failure of one capacitor in a bank frequently results in an explosion when all other capacitors in the bank discharge into the fault.

Why are capacitors used in high voltage cables?

Capacitors may be used to store large amounts of energy. An internal failure of one capacitor in a bank frequently results in an explosion when all other capacitors in the bank discharge into the fault. Note: High voltage cables should be treated as capacitors because they have capacitance and thus can store energy.

What happens if a capacitor is de-energized?

Capacitors may store hazardous energy even after the equipment has been de-energized, and may build up a dangerous residual charge without an external source. "Grounding" capacitors in series, for example, may transfer (rather than discharge) the stored energy.

Should high voltage cables be treated as capacitors?

Note: High voltage cables should be treated as capacitors because they have capacitance and thus can store energy. The liquid dielectric in many capacitors, or its combustion products, may be toxic. Use permanently connected bleeder resistors when practical. Capacitors in series should have separate bleeders.

How do you protect a capacitor?

Protection also must be provided against the hazard of the discharge itself. Provide fully visible, manual-grounding devices to render the capacitors safe while they are being worked on. Clearly mark grounding points and use caution to prevent transferring charges to other capacitors. All grounding hooks must: Have crimped and soldered conductors.

What happens if a capacitor fails in a bank?

An internal failure of one capacitor in a bank frequently results in an explosion when all other capacitors in the bank discharge into the fault. Note: High voltage cables should be treated as capacitors because they have capacitance and thus can store energy. The liquid dielectric in many capacitors, or its combustion products, may be toxic.