To protect electrical wiring from damage due to exterior causes, an electrical conduit is installed. This piping system also serves as a wiring router since it provides a defining shape for the electrical wiring installation. An electrical conduit is installed by qualified electricians and is regulated by the National Electrical Code (NEC).

Common materials

An electrical conduit uses various materials to provide mechanical protection of the interior wiring. Depending on the environment on which the electrical conduit is used, this protective layer can be made of fiber, metal, or plastic. The varying degrees of flexibility and durability of these materials serve different wiring requirements. For instance, rigid metal or plastic are ideal for maximum protection but these non-flexible electrical conduits may be difficult to install in certain areas. Flexible conduits, on the other hand, are used in locations where rigid conduits are difficult to maneuver.

One of the most popular electrical conduits is Southwire’s Flexible Aluminum Conduit:

Our electrical supply store has a variety of other conduits and conduit fittings for any electrical job or project.

Types of electrical conduit

Most electrical conduit falls into one of the following categories:

The different types of piping system are classified according to the kind of material used and the purpose it specifically serves. Rigid metal conduit (RMC) is characterized by its thick threaded tubing made of steel or aluminum. Rigid nonmetallic conduit (RNMC), on the other hand, is made from nonmetallic materials such as fire clay and, thus, is unthreaded.

Also called a thin-wall, electrical metallic tubing (EMT) is a cheap alternative to conventional piping systems. It is made of coated steel and sometimes aluminum. A similar type is the electrical nonmetallic tubing (ENT), which is corrugated with strong resistance against moisture and fire. One particular advantage of ENT is that it can be shaped by hand.

Polyvinyl chloride or PVC pipe is distinguished as the lightest of all types and usually lower in cost. A PVC pipe is available in varying thicknesses. The thin-wall PVC pipe is used for wirings embedded in concrete while thick-wall PVC pipe is used for wirings buried beneath the ground. Exposed wirings also use the thick-wall PVC pipe variety.

One great advantage of PVC pipe is its resistance against moisture and other corrosive substances. Conduit fittings can also be made out from the same material as the PVC pipe making the installations more compatible. A PVC pipe can also be bent easily by just heating the material providing convenience for remote installations. Despite all these advantages, the non-conductive PVC pipe requires an extra bonding conductor for grounding.

Conduit fittings

Two ends of an electrical conduit are connected via conduit fittings. These purpose-designed conduit fittings are similar to the conventional pipes used in plumbing. Types of conduit fittings commonly employed are box connectors and couplings. Box connectors used as conduit fittings join several ends of an electrical conduit in a junction box, also called the electrical box. Couplings, on the other hand, as conduit fittings are different from box connectors in that only two ends of an electrical conduit can be joined.

Installation of an electrical conduit as well as choosing the right material is a serious consideration in a building or project’s electrical safety. The appropriate conduit fittings must also be chosen.  Carlon makes a great offset conduit fitting to match PVC conduit:

Among the different conduit materials, PVC pipe has several advantages that make it the generally preferred choice. However, each job has individual needs and if you find yourself stumped please contact a qualified electrician to get professional advice.