This section contains the requirements for equipment and installation (including manholes, switch vaults and pull boxes) relating to the Sub-transmission, Distribution, and Control of electric power ranging from 600-Volts to 25,000-Volts, such as substations . This section contains the requirements for equipment and installation (including manholes, switch vaults and pull boxes) relating to the Sub-transmission, Distribution, and Control of electric power ranging from 600-Volts to 25,000-Volts, such as substations . Contactors: Contactors are used to switch o and to switch on loads requiring these operations during normal use, especially as used in a particular activity such as the MV public lighting and industrial motors. Current-limiting fuses: MV current-limiting fuses are primarily used in protection of. This document sets forth technical, installation and safety specifications for distribution boxes, switch boxes and cabinets. It stipulates requirements for enclosure materials, installation dimensions, the mandatory "one equipment, one switch, one RCD" rule, mechanical structure, earthing systems. However, the key to a safe and reliable system lies in proper installation. If it's done poorly, you risk short circuits, fire hazards, or system failure. Done right, it ensures safety, compliance, and long-lasting performance.