Test 2 Conduit

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Groups of raceways

Mount on strut-type channels, and secure in place with strut-type channel straps identified for the particular channel and raceways. Channel shall be fastened in place by means suitable to the mounting surface.

Uses Permitted to install EMT (Corrosive Environments)

1) Galvanized steel and stainless steel EMT, elbows, and fittings shall be permitted to be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosion protection and approved as suitable for the condition. 2) Supplementary Protection of Aluminum EMT - Aluminum EMT shall be provided with approved supplementary corrosion protection where encased in concrete or in direct contact with the earth. 3) Cinder fill - Galvanized steel and stainless steel EMT shall be permitted to be installed in cinder concrete or cinder fill where subject to permanent moisture concrete at least 2" thick or when the tubing is installed at least 18" under the fill. 4) Wet locations all supports, bolts straps, screws, and so forth shall be of corrosion-resistant materials or protected against corrosion by corrosion- resistant materials.

Rigid Conduit with PVC coating

3 types of PVC-coated conduit; couplings are supplied separately. 1) Primary PVC coating over bare steel which is listed rigid conduit for environmentally suitable locations. 2) A PVC coating over listed galvanized steel conduit. This is supplementary coating intended for added protection in severely corrosive locations. 3)A primary PVC coating over a supplementary coating of zinc. This is also intended for severely corrosive locations.

Raceways suspended below ceiling or structural members such as beams, columns, purlins, or ceiling cavities

Best supported in lay-in pipe hangers. Pipe hangers are supported by threaded rod which is fastened in place by beam clamps. Strut type channel can also provide support. Raceways are not permitted to lie on the ceilings. In fire rated ceiling cavities support by the ceiling wires is not permitted unless tested as part of the fire rated assembly. A separate support system must be installed for the conduit.

Steel or PVC Conduit

Can provide mechanical protection against forces from the outside and from within itself. Metallic can provide a high degree of fire protection as well as the ability to safely contain overloaded or short-circuited conductors that could cause or contribute to a fire. PVC are used in highly corrosive areas/conditions

Flexible metal conduit

Combines mechanical protection with maximum flexibility for non hazardous locations. It's flexibility allows it to be used in close working conditions. Can be used in connections to motors due to the vibration factors, and connection of lighting fixtures.

Conduit type EMT

Commonly called thin wall nominally 10' long. Trade size 1/2" to 4". Installed by the use of set screw or compression type couplings or connectors.

Rigid PVC Conduit

Completely aplastic material. Used in severely corrosive locations that do not require the strength or other qualities of PVC coated rigid steel. PVC does not conduct Electricity. A grounding conductor must be installed. PVC is solvent welded together.

Conduit Installations

Conduit systems should be completed before installing wire.Before pulling wire reaming should be done so there are no sharp edges.

Conduit Applications

Conduit wiring systems are used for wiring in apartments, factories, garages, etc. It can be buried directly in masonry construction. if installed properly it can be watertight and vapor tight.

Markings

EMT shall be clearly and durably marked at least every 10'

Construction Specs

EMT shall be made of Steel with protective coatings, Aluminum, Stainless Steel

Grounding

EMT shall be permitted as an equipment grounding conductor

Splices and taps

Fittings and connectors shall be used only with specific wiring methods for which they are designed and listed. a box or conduit body shall be installed at each conductor splice point, outlet point, switch point, unless otherwise permitted.

Supporting

Horizontal runs of EMT supported by openings thru framing members at intervals not greater than 10' and securely fastened within 3' of termination points shall be permitted.

Conduit Type IMC

IMC is listed steel raceway of circular cross section with a coupling, which can be either standard straight tapped conduit coupling or the integral type. Threaded ends are protected by color coded plastic covers which keep the clean, sharp, and help aid in trade size recognition. IMC is available in trade sizes 1/2" thru 4". Thinner than RMC and weighs about 1/3 less.

Uses Permitted to install EMT (Exposed and Concealed)

In concrete, in direct contact with the earth or in areas subject to severe corrosive influences

Liquid Tight Flexible Metal Conduit

Is a PVC jacketed flexible metal conduit. Normally used in damp locations and corrosive environments where a flexible yet moistureproof wiring method is needed.

Raceway exposed on masonry surfaces, plaster, drywall or wood framing members

One or two hole straps, conduit hangers, or similar products intended for the purpose, securely fastened with appropriate hardware. Conduit 1/2"to 1" can be supported by nail straps in wood framing

Raceway mounted on metal framing members

One or two hole straps, conduit hangers, or similar products intended for the purpose, securely fastened with metal screws or rivets. When using clamp-on supports add screws, rivets, beam clamps, or similar means for extra support, unless the clamp on supports are the hammer on or press type

Conduit

Provides mechanical protection for the wiring system and to minimize the possibility of electrical hazards to person and property. Can allow for future updating for future expansion or wiring changes.

Conduit type RMC

RMC is produced in aluminum or steel. RMC is listed threaded metal raceway of circular cross section with a coupling, which can be either standard straight tapped conduit coupling or the integral type. Threaded ends are protected by color coded plastic covers which keep the clean, sharp, and help aid in trade size recognition.RMC is available in trade sizes 1/2" to 6". RMC can have a primary coating of zinc, a combination of zinc and organic coatings, or a non metallic coating of PVC. RMC is the heaviest and thickest conduit. Galvanized RMC has no temperature limitations and can be used indoors, outdoors, underground, concealed, or exposed.

Conduit sizes

Usually produced in 10' lengths. Trade sizes from 1/2" up to 6"

Uses not permitted to install EMT

Where subject to severe physical damage and for the support of luminaries or other equipment except conduit bodies no larger than the largest trade size of the tubing

Coupling and Connectors

... used with EMT shall be made up tight. Where buried in masonry or concrete, they shall be concrete tight type. Where installed in wet locations shall prevent moisture, listed for use in wet locations, approved drainage openings not smaller than 1/8" and not larger than 1/4". Larger openings are allowed in accordance with manufacturer's instructions.

Minimum and Maximum Trade size for EMT

1/2" up to Trade size 4

T Condulet

3 Openings and looks like a T

Reaming

All cut ends of EMT shall be reamed or otherwise finished to remove rough edges

LB Condulet

Back has a opening

Bends - How Made

Bends shall be made so that the tubing is not damaged and the internal diameter of the tubing is not effectively reduced. The radius of the curve of any field bend to the centerline of the tubing shall not be less than shown in Table 2 Chapter 9 for one shot and full shoe benders

Securing

EMT shall be securely fastened in place at intervals not exceeding 10'. In addition, each EMT run between termination points shall be securely fastened within 3' of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination.

Fire-stopping and fire blocking

NEC and building codes require that openings around raceways which penetrate a fire-rated assembly be sealed, to prevent smoke, gases and flames from one area migrating to another. Most building codes permit openings around galvanized steel RMC, IMC, and EMT in concrete or masonry to be filled with cement, motor, or grout. Local building codes can vary and should be checked before installation. In all cases, the raceway installer shall use materials which assure that fire ratings of the penetrated assembly area are not degraded by the installation of a raceway system.

Threading

Shall not be threaded. Exception EMT with factory threaded integral couplings

LR Condulet

Straight piece is on the Right

LL Condulet

Straight piece is on the left

Maximum Conductors

Table 1 Chapter 9

Bends - Number in one run

There shall not be more than the equivalent of four quarter bends (360 degrees total) between pull points, for example conduit bodies and boxes.

Electrical Metallic Tubing (EMT)

Unthreaded thin wall raceway of circular cross section designed for the physical protection and routing of conductors and cables and for use as an equipment grounding conductor when installed utilizing appropriate fittings

RMC,IMC, and EMT

are not required to have fire ratings because building codes define these galvanized steel raceways as noncombustible. Listed fire-stopping systems shall be used to fill the penetrations around metallic raceways.

"C" Condulet

openings on both ends

Dissimilar Metals

shall be avoided to eliminate the possibility of galvanic action. Aluminum fittings and enclosures shall be permitted to be used with galvanized steel EMT, and galvanized steel fittings and enclosures shall be permitted to be used with aluminum EMT where not subject to severe corrosive influences. Stainless steel EMT shall only be used with stainless steel fittings and approved accessories, outlet boxes, and enclosures


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