Comprehensive Guide to Capacitor Technology and Safety Mechanisms
Table of Contents
Capacitor Technology: Properties, Safety, and Application Insights #
Technical Resources and Downloads #
- Automatic Capacitor Bank Wiring Diagram
Download: PDF | DWG - Installation of Capacitor Expulsion Fuse
Download: PDF - Capacitor Expulsion Fuse Unit
Download: PDF
Electrical Properties of Metallized Film Capacitors #
Self-Healing Mechanism #
Metallized film capacitors utilize a self-healing process. When excessive voltage causes localized damage, the metallized layer around the affected area vaporizes, instantly restoring insulation. This mechanism ensures continued operation and reliability.
- 1. Metallized layer
- 2. Film
- 3. Damaged spot
- 4. Self-healing range
Safety Features in Capacitor Design #
Internal Safety Mechanism #
Capacitor elements are constructed using segmented metallized film, forming hundreds or thousands of small capacitors in parallel. Each small capacitor is equipped with an individual fuse:
- If a dielectric breakdown occurs due to overvoltage, abnormal heating, or end-of-life, the fuse in the affected area burns out, disconnecting it from the circuit.
- The remaining functional capacitors continue to operate, maintaining overall performance.
- This self-protective feature prevents the capacitor from emitting smoke or catching fire.
- 1. Segmented metallized film
- 2. General metallized film
- 3. Metallized layer
- 4. Free margin in transverse direction
- 5. Free margin in machine direction
- 6. Fuses
- 7. Failure area
Internal Protective Device Operation #
As capacitors age or experience internal failure, repeated self-healing breakdowns can increase internal pressure. To prevent bursting:
- Each element is equipped with a pressure-sensitive interrupter (protective device).
- Rising pressure causes the cover to bulge, disconnecting copper taps at designated weak points.
- The current path is irreversibly interrupted, ensuring safety and preventing hazardous outcomes.
Technical Support and Application Guidance #
- Capacitor function
- Notices for capacitor installation
- Benefits of shunt capacitors
- Selection references for protective devices (low voltage capacitors)
- Benefits of shunt capacitors at different locations
- Capacitor maintenance
- Selection principles for power factor correction capacitors (industrial high/low voltage systems)
- Power factor correction calculation
- Harmonics strategies for power capacitors
- General formulas
- Resonance point and frequency calculation for capacitors with series reactors
- Discharging resistor calculation for capacitors
- Power capacitor instructions
- Features of low voltage power capacitors
- Causes of capacitor faults
- Heat dissipation instructions for induction heating furnace capacitors
- Effects of lightning strikes on capacitors
- Circuit diagrams for automatic PFC capacitor banks
- Correct connection of capacitors for star-delta starting induction motors
- Parts and dimensions of expulsion fuses for power capacitors
For further technical assistance or inquiries, please contact us.