The capacitors in NEPSI's Metal-Enclosed Capacitor Banks and Harmonic Filter Banks are individually fused to protect against case rupture and capacitor failure due to dielectric and non-dielectric capacitor faults. Fuses are sized to withstand transient inrush currents associated with back-to-back capacitor bank switching.

Fuses are equipped with blown fuse indicators. These indicators are visible through the enclosure window. The current limiting fuses have a short circuit rating to 50kA and expel no gases during operation. In most banks, fuses are bolted in, but clip style fuses can be provided as an option.

As a guideline for fuse selection, consult NEPSI's technote titled "Current Limiting Fuse Selection for Medium Voltage Capacitors".

• Voltage Rating - Fuse voltage rating is chosen based on system voltage and expected fuse voltage before and after fuse interruption..
  
  
• Current Rating - Fuse current rating is chosen such that it does not blow for back-to-back capacitor bank switching transients.
  
  
• Short Circuit Rating - Fuse short circuit rating is chosen such that it is greater than the available short circuit current at the capacitor terminals. Fuse fault rating of 50kA is rarely obtained.
  

  Fuse Product Literature

  Table 1 - Available Product Literature and Time Current Curves
  Adobe Acrobat Files	Cooper NXC Current Limiting Fuse
  Adobe Acrobat Files	Cooper X-Limiter Capacitor Fuse Time-Current Curves
  Adobe Acrobat Files	Cooper NX Fuse Time-Current Curves