It can be used in indoor systems for 50 Hz, with rated voltages of 3.6 kV, 7.2 kV, 12 kV, 24 kV, and 40.5 kV. When used in conjunction with other switchgear such as load switches and vacuum contactors, it protects electrical transformers and other electrical equipment against overloading or circuit breakers. It is also an essential accessory for high-voltage switchboxes, ring main units, and high/low-voltage top-mounted substations.