An electrical conduit is a tube used to protect and rou […]
An electrical conduit is a tube used to protect and route electrical wiring in a building or structure. It is generally installed by electricians at the site of installation of electrical equipment and its specifications are regulated by the US National Electrical Code (NEC). An electrical conduit is made of metal, plastic, fiber or fired clay. Most conduit is rigid, but it can be flexible as well.
While metallic conduits serve to shield sensitive circuits from electromagnetic interference from enclosed power cables, non-metallic conduits resist corrosion and are lightweight, reducing labor and installation costs. Read on to find out more about different types of non-metallic conduits.
PVC Conduit: this has been considered the lightest weight and lowest cost when compared to other types of conduits. In North America, it is available in three different wall thicknesses. The thin wall variety is suitable only for embedded use in concrete, while heavier grades are suitable for direct burial and exposed work. The various fittings made for metal conduit are also available in PVC form.
PVC conduit is heated and bent in the field using special tools. These include joint to fittings that are made with slip-on solvent welded connections. These set rapidly after assembly and attain full strength in about one day. Since the slip fit sections do not need to be rotated during assembly, the special union fitting used with threaded conduit is not required. Because PVC conduit has a higher coefficient of thermal expansions that other types of conduit, it must be mounted to allow expansion and contraction.
When installing PVC underground in multiple or parallel run configurations, proper methods should be executed to avoid deformation when heated, due to the mutual heating effect of densely packed cables.