When it comes to electrical wiring in residential and commercial buildings, there are three main types of conduit used: rigid metal conduit (RMC), intermediate metal conduit (IMC), and electrical metallic tubing (EMT). Each type has advantages and disadvantages that make it more or less suitable for different applications. In this article, we'll take a closer look at each type of EMT conduit and determine when it's best to use them.
EMT Conduits EMT (electrical metallic tubing) is a conduit installed outside a house or building to protect the wiring inside from physical damage and moisture. It is made from a galvanised steel tube that has been threaded on both ends and has a protective plastic coating. EMT can be used for various applications, from running electrical wires to lighting fixtures and appliances within the home to carrying cables and pipes in commercial buildings. EMT is also used in most electrical and lighting installations.
Types of EMT: rigid, flexible
Rigid EMT is the most common and is used to run electrical wire and cable through a building. It's available in straight sections of varying lengths and pre-formed 90-degree elbows and 45-degree bends. It is also available in various diameters and can be purchased with cable or wire already inside. Flexible EMT (or rigid conduit) is used for running wires under floors, ceilings, and walls.
Rigid EMT: steel, aluminium
Steel EMT is the most common type. It is either galvanised or non-galvanized. Galvanization protects steel against corrosion but can be scratched and marred easily. Aluminium is lighter than steel but more expensive.
Flexible EMT: non-metallic, plastic-coated
Conventional flexible EMT is a black, non-metallic material that can be used to carry both electrical and communication cables. It is used for running wires under floors, ceilings, and walls. Pliable EMT is a plastic-coated version of conventional flexible EMT. It is used for running telephone and data cables. Rigid cable non-metallic, plastic-coated PVC, or polyvinyl chloride, and PCTFE, or polychlorotrifluoroethylene, are the most common types of rigid cable.
Comparison of types of EMT: cost, installation, durability
Conventional flexible EMTs have the advantage of being less expensive than rigid cables. However, it is not as pliable as rigid cable and can be damaged if bent too sharply. Rigid cable is more expensive, but it is more durable and pliable. The rigid cable is also highly resistant to water, chemicals, and temperature extremes.