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Pressure valves on aluminum electrolytic capacitors

The pressure vent on an aluminum electrolytic capacitor is installed to mitigate the risk of ruptures or dangers caused by an increase in inner pressure during a malfunction.
The risk of inner pressure increases as the accumulated energy in the aluminum electrolytic capacitor increases. For this reason, the pressure vent plays a particularly critical role in large-sized aluminum electrolytic capacitors.
Among the products we offer, we install pressure vents on surface mount type products with a diameter of ⌀10mm or larger, on radial lead type products with a diameter of ⌀8mm or larger (and on certain ⌀6.3mm products), and on all large-sized aluminum electrolytic capacitors (snap-in type, screw terminal type).
The main reason small-sized products do not have pressure vents is because they have a low levels of accumulated energy.
  • Product diameter (mm) of aluminum electrolytic capacitor with a pressure vent: (examples from product catalog)
    Type Applicable size
    SMD type ⌀10mm and above
    Radial Lead type ⌀8mm and above
    (and on certain ⌀6.3mm products)
    Snap-in type All size
    Screw terminal type All size
Ensure the following space above the capacitor to prevent triggering the pressure vent on capacitors with a pressure vent.

Pressure vent upper clearance
Case diameter Clearance
⌀8(6.3) to ⌀16 2mm minimum
⌀18 to ⌀35 3mm minimum
⌀40 and above 5mm minimum

If you have any questions or inquiries that do not apply to the above, please contact us at the following address.

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