20kV-2000pF 30kV-1000pF 40kV-150pF High Voltage Doorknob Capacitor and Doorhandle Capacitor for Lightning Arresters

Selection Guide - How to Choose a Doorhandle Capacitor for Your Lightning Arrester
Improperly selected capacitors can become the weak link in the protection chain. In engineering practice, the following parameters should be evaluated:

Rated voltage: Should be 20% higher than the system's maximum continuous operating voltage (Uc). For example, a 480V system is recommended to use 520V or higher.

Capacitance Value and Pulse Withstand: Select a capacitance value based on the required discharge energy (typical range: 100pF–0.1µF) and ensure that the capacitor can withstand the nominal discharge current (e.g., 20kA/8/20µs) and multiple surges.

Low Equivalent Series Inductance (ESL): The ESL value should be ≤20nH to avoid pulse response delays.

Environmental Adaptability: For coastal areas, IP68 sealing rating is required. For high altitudes (>2000m), the Uc reduction rule of 1% for every 100m increase in altitude should be applied. For wind turbine converter cabinets, for example, epoxy-encapsulated doorhandle capacitors with screw terminals ≥4mm deep are recommended to ensure reliable connection in vibration environments.