ABSTRACT
The provisions here apply to the installation and use of high-voltage power distribution and utilization equipment that is portable or mobile, such as substations, trailers, cars, mobile shovels, draglines, hoists, drills, dredges, compressors, pumps, conveyors, and underground excavators. Conductors in tunnels must be installed in
• Metal conduit or other metal raceway • Metal-clad (MC) cable • Other approved multiconductor cable
Multiconductor portable cable may supply mobile equipment. Conductors and cables must be located or guarded as protection against physical damage. An equipment grounding conductor must be run with circuit conductors inside the metal raceway or inside the multiconductor cable jacket. The equipment grounding conductor may be insulated or bare. Bare terminals of transformers, switches, motor controllers, and other equipment must be enclosed to prevent accidental contact with energized parts. Enclosures for use in tunnels must be drip-proof, weatherproof, or submersible as required by the environmental conditions.
