Which statement about portable multiconductor cable is correct in tunnel applications?

Which statement about portable multiconductor cable is correct in tunnel applications?

• A. A portable multiconductor cable is permitted to supply mobile equipment
• B. Portable multiconductor cable is never permitted
• C. Portable multiconductor cable is only for temporary use
• D. Portable multiconductor cable must be enclosed in metal conduit

Answer: (A)

Portable multiconductor cables are meant to provide flexible, movable power to equipment in places like tunnels, where fixed wiring to every location isn’t practical. In tunnel work, you often need to relocate or reposition mobile equipment, and these cables are designed to handle that kind of use, as long as the installation follows the relevant ratings and protection requirements. That’s why this statement is the best: it reflects that portable multiconductor cables can be used to supply mobile equipment in tunnel settings, rather than being completely prohibited or restricted to one narrow use. They aren’t inherently required to be enclosed in metal conduit in every case, and they aren’t limited to temporary, one-off use—their purpose includes powering movable equipment over the course of the project, with appropriate safety measures. The other options are too absolute or restrictive: “never permitted” isn’t correct because portable cables are commonly used to power movable equipment; “only for temporary use” is overly limiting for ongoing movable equipment needs; and “must be enclosed in metal conduit” isn’t a universal requirement for portable cables, as protection can be achieved in other approved ways depending on the installation.

Portable multiconductor cables are meant to provide flexible, movable power to equipment in places like tunnels, where fixed wiring to every location isn’t practical. In tunnel work, you often need to relocate or reposition mobile equipment, and these cables are designed to handle that kind of use, as long as the installation follows the relevant ratings and protection requirements.

That’s why this statement is the best: it reflects that portable multiconductor cables can be used to supply mobile equipment in tunnel settings, rather than being completely prohibited or restricted to one narrow use. They aren’t inherently required to be enclosed in metal conduit in every case, and they aren’t limited to temporary, one-off use—their purpose includes powering movable equipment over the course of the project, with appropriate safety measures.

The other options are too absolute or restrictive: “never permitted” isn’t correct because portable cables are commonly used to power movable equipment; “only for temporary use” is overly limiting for ongoing movable equipment needs; and “must be enclosed in metal conduit” isn’t a universal requirement for portable cables, as protection can be achieved in other approved ways depending on the installation.