Replacement period of capacitor fuse

Are capacitor fuses capacitive limited?

Most capacitor fuses have a maximum power frequency fault current that they can interrupt. These currents may be different for inductive and capacitively limited faults. For ungrounded or multi-series group banks, the faults are capacitive limited.

How do capacitor current limiting fuses work?

Capacitor current-limiting fuses can be designed to operate in two different ways. The COL fuse uses ribbons with a non-uniform cross section. This configuration allows the fuse to be used to interrupt inductively limited faults. The pressure is generated by the arc contained in the sealed housing.

How does a capacitor fault affect a fuse?

Either of these two effects can impede the proper operation of the fuse. In the event of a capacitor fault, excess current will flow through the fuse of the faulted unit. This current causes the fuse element to melt and vaporize. An arc will form across the vaporized section within the fuse tube.

What is a capacitor fuse used for?

The fuse, by its design, avoids absorbing all of the available energy on the series group. This fuse is used for capacitor banks with a large number of parallel capacitors. It can be used on applications with essentially infinite parallel stored energy, as long as sufficient back voltage can be developed to force the current to extinguish.

What is a CIL current limiting capacitor fuse?

The CIL current-limiting capacitor fuse has a two-part design. The high current section interrupts high 60 Hz fault currents and/or high frequency discharge current from parallel capacitors. The low voltage section consists of a standard NEMA Type K fuse link mounted in a fiber tube.

What is a capacitor fusing factor?

The capacitor must be able to absorb this energy with a low probability of case rupture. Fuses are usually applied with some continuous current margin. The margin is typically in the range of 1.3 to 1.65 per unit. This margin is called the fusing factor.