Nichicon Application Guidelines for Aluminium Electrolytic Capacitors
Nichicon Technical Notes CAT.8101H, Application Guidelines for Aluminum Electrolytic Capacitors, prepared in accordance with the JEITA/EIAJ RCR-2367D guideline. A manufacturer document rather than a hobbyist one, and the reference this wiki uses for what a failing electrolytic actually does.
What is in it
[edit | edit source]- Venting: capacitors above a certain size have a pressure relief vent. What comes out is vaporised hydrogen and electrolyte at over 100 degrees C - it is not smoke from combustion. Keep your face away; flush eyes with water if you are caught by it.
- First aid: wash skin exposed to electrolyte with soap and water.
- Do not expose capacitors to acidic or alkaline solutions. Nichicon publishes no pH for the electrolyte and recommends washing, not neutralising.
- Storage: 5 to 35 degrees C and 75 per cent relative humidity or less.
- Disposal and removal: discharge the capacitor before removing it from the board.
- Failure modes: short circuit (rare in the field), open circuit (lead/tab damage, halogen ingress from flux or cleaning agents, electrolyte loss through the seal), capacitance drop and high ESR (reverse voltage, excessive ripple, extreme charge/discharge), and pressure-relief vent operation.
Download: Nichicon Application Guidelines for Aluminium Electrolytic Capacitors.pdf