NEPSI's Metal-Enclosed Capacitor Banks and Harmonic Filter Banks are equipped with an incoming air disconnect switch and ground switch to allow for safe isolation from the power system during maintenance. These switches are located in an isolated compartment (behind an internal swingout door) to allow for safe entry into the main incoming fuse compartment and capacitor compartment without inadvertent contact with live terminals/cables.

The air disconnect switch is not intended for load interruption, and therefore is an integral part of the capacitor bank key interlock system. Load interruption is dictated by the key interlock sequence and is provided by the banks vacuum switches/contactors.