13 — Cable junction boxes

25 — Shallow/Deep Low-Voltage MCCs and Panelboards

32 — Low-Voltage Switchgear

VCB — Vertical conductors in a metal box/enclosure. With the original vertical electrode configuration, when an arc flash occurs in an enclosure, the arc is driven away from the source, down the electrodes, toward the bottom of the enclosure and out of the front.

VCBB — Vertical conductors terminated in a metal box/enclosure’s insulating barrier. If vertical electrodes are terminated into an insulating barrier, research has demonstrated the arc hits the barrier, and the plasma cloud is directed more toward the enclosure opening.

HCB — Horizontal conductors in a metal box/enclosure. When the electrodes are placed horizontally, the arc plasma is directed from the electrode ends outward.

Defines the voltage in Vac.

Defines the available fault current in kA – range from 0.5kA to 106kA. For available fault currents above 106kA, use 106kA.

Defines the fuse amperage rating. For fuses above 2500A, arc energy reduction is required.