To cut it yourself, you'll need a hacksaw or a pipe cutter and possibly a clamp or vise to keep it from moving. After cutting and before conduit installation , you'll need to file the sharps edges down and thread the conduit so you can use threaded couplings, locknuts and bushings. To bend rigid-steel conduit, you can use a manual bender or have it factory bent, however factory bending is much more expensive.
For installing conduit in damp areas or underground, galvanized steel conduit is used to prevent moisture and rusting. To cut electric metallic tubing conduit, you'll need a hacksaw or tubing cutter and possibly a clamp or vise to keep it from moving. After cutting you'll need to file the sharps edges down before installing conduit. Rigid Nonmetallic Conduit also known as PVC conduit is made of a rugged plastic and thus is ideal for underground conduit installations including direct burial and concrete encasement installation.
Installing conduit that is made out of plastic is cheaper, plus it's strong, waterproof and has a low absorption rate. To cut it, you'll need a hacksaw or tubing cutter and possibly a clamp or vise to keep it from moving. After cutting, you'll need to file the sharps edges down. Flexible metallic conduit is made of either steel or aluminum and typically used for conduit installation in areas where there may be movement or vibration. You can also get it for use in wet conditions.
To cut it, you'll need a hacksaw and possibly a clamp or vise to keep it from moving. When installing conduit make your runs of conduit as straight and direct as possible and avoid any unnecessary bends.
Concrete-tight and water-tight connectors and couplings are also required for concrete and wet applications respectively. You can get threaded or threadless couplings and connectors for rigid-steel and PVC conduit.
With threadless, there is no threading of the conduit required. EMT conduit is too thin and cannot be threaded, therefore uses only threadless couplings and connectors. On rigid steel conduit installation, threaded couplings are screwed onto the threaded ends of the conduit and a pipe wrench is used to tighten them.
Rigid-steel and PVC conduit is connected to electrical boxes using locknuts and bushings. Fittings for flexible metallic conduit are attached to the conduit either by screwing them on internally or with clamping screws externally. For installing conduit in wet areas, liquid-tight fittings are used. The next part of the process involves connecting the conduit pieces together.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website. This article series describes both metallic electrical conduit and plastic or non-metallic electrical conduit products, and answers basic questions about installing electrical conduit. Electrical conduit is metal or plastic rigid or flexible tubing used to route electrical wires in a building.
The page top photo showing rigid conduit used to bring wires up to an electrical sub-panel was provided courtesy of Tim Hemm. Watch Out : Do not attempt to work on your electrical wiring, switches, or outlets unless you are properly trained and equipped to do so. Elecdtrical components in a building can easily cause an electrical shock, burn, or even death.
Even when a hot line switch is off, one terminal on the switch is still connected to the power source. Electrical conduit for wiring has some advantages in protecting wires and also in running multiple wires to a location. The proper selection of electrical conduit materials, fittings, and installation are important for safe electrical wiring. Both flexible electrical conduit and rigid conduit were used.
Our arrow points to an improper "bend" made in the rigid metal electrical conduit. Steel electrical conduit and tubing EMT have been used for many decades to protect electrical wiring from mechanical damage and to provide electromagnetic field or electromagnetic interference shielding for circuits and wiring of various types.
The range of electrical conduit materials and properties is large and is designed both for special applications such as corrosion or moisture resistance. The most common type of electrical conduit for house wiring is the thin-wall type. Thin-wall conduit is too thin for threaded joints. It is joined to other lengths of conduit and to boxes by pressure-type fittings. Stainless steel EMT conduit and fittings combine strength with ductility, resulting in an affordable, lightweight and easy-to-handle conduit assembly.
Thin-wall conduit is sold in ten-foot lengths in either one-half inch or three-quarter inch outside diameter. The one-half inch conduit can contain four No. Three-quarter inch conduit accommodates four No. These wire capacities are for individual wires , not pairs. The wires used are the same as the individual conductors found in steel armor cable and plastic sheathed cable.
Wires in conduit must follow standard coding. In a two-wire electrical circuit you need one black wire, one white wire, and one ground wire. The general procedure for using thin wall conduit is similar to the use of steel armor cable. The big difference is that conduit cannot be "snaked" through openings in ceilings and walls. You must have full access to joists and studs to install electrical conduit. So you probably won't want to use it unless your local code requires it.
In the U. The conduit fill listed under thin-wall metal conduit [above] is wrong. Granted, under normal conditions, you generally cannot go over 9 current carrying conductors in a conduit without needing to reduce its current carrying capacity below the size circuit for which it is generally used e.
NEC Table C. Flexible metallic electrical conduit is used principally in commercial and industrial construction world wide. In residential applications you may find FMC used to connect an electric oven or electric cooktop. LFMC is described in the U. Flexible metal conduit is sold in rolls and cut to the necessary length, joined with appropriate fittings.
Intermediate Metallic Conduit or IMC is lighter weight, metallic conduit and is rated as stronger than other rigid conduit. IMC, provided in both threaded IMC and non-threaded IMC forms, is a rigid metallic conduit tubing, typically hot-dipped galvanized steel or stainless steel.
The interior of galvanized steel IMC is usually coated with an anti-corrosion layer. Threaded IMC is joined by threaded couplings, C condulets, sweeps and bends. The tubing is cut with a pipe cutter or tubing cutter, and then threads cut using a thread cutting tool. When cutting IMC, take care to remove burrs on the tubing interior that would otherwise damage electrical wires being pulled through the conduit. IMC is typically used in hazardous locations, and in its stainless steel formulation, IMC is widely used in the food and beverage industry, in chemical plants, in cosmetic and pharmaceutcial industries, in refineries, in pulp and paper mills, in marine and coastal sites, in other corrosive environments.
An advantage of IMC is its larger interior diameter compared with RMC of the same nominal sizes, making it easire to pull wires. There the flexible whip avoids problems with vibration-loosened connections in the conduit.
Watch out : Flexible conduit and whips are "flexible" but not to degrees that exceed the laws of physics and the properties of the materials. If you force flexible conduit or a pre-wired conduit whip to bend too acutely over too short a radius such as at its connection to a rigid surface the conduit will eventually break, as Tim Hemm's photograph left illustrates.
Rigid metal conduit is a heavier gauge steel electrical conduit using threaded couplings and fittings and is the thickest, or stiffest of the conduit materials used for electrical wiring. A typical RMC and often the only RMC residential application is to enclose the electrical service entry wiring from the electrical company's overhead wires at the mast-head down to the electrical panel mounted on the building wall.
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