How Much Do You Know About Armored Cable ?

Armored cable is a conductive cable covered by a metal sheath. In most cases, it consists of a bundle of wires wrapped in a metal tube, possibly covered by plastic insulation. Although a specific cable type is properly called armored cable, the term is often used as a general reference to all metal-covered power cables. There are actually three basic forms of metal-clad cable, each with its own characteristics.

Various types of metal-clad cables are manufactured in a similar manner. The heart of the cable is the wire harness. These copper wires are covered with their own plastic insulation that separates them from the metal cover and from each other. For metal overlays, it protects the wiring harness from physical shock and abrasion. The metal is generally a long strip of metal wrapped around the cable; this gives the metal covering a corrugated, spring-like appearance.

There are three basic types of metal-clad cables; all are referred to as armored cables. BX is the oldest form. While this cable provides the protection commonly found in armored cables, it has a tendency to leak, and it has a poor grounding system.

True armored cable is essentially just a heavier form of BX. It has a better grounding system and heavier internal insulation. The process used to coat the cable in its metal covering allows for better water resistance and an overall stronger design.

The last type of armored cable is the metal clad (MC) cable. MC cables use a different grounding system than true armored cables and may have additional water resistance. This is the latest type of metal clad cable widely used in commercial and industrial buildings.

The differences between the three cable types are very small and often unclear, but the biggest difference is the grounding system of the cable. BX cables are usually grounded through a metal jacket, which works well if the cable is buried or covered in some way, but not so well if it's exposed. Armored cables are also grounded through the jacket, but have the ability to be grounded to a predetermined area, which allows certain parts to be exposed without exposing the grounding system. Finally, there are ground wires within the MC cable harness, allowing the user to create ground wires wherever needed, making the system safe in exposed areas.