Electrical Level 1 Raceways and Fittings 26108 17

  • Slides: 33
Download presentation
Electrical Level 1 Raceways and Fittings 26108 -17

Electrical Level 1 Raceways and Fittings 26108 -17

Sessions 2 & 3: Bonding Conduit; Metal Conduit Fittings Raceways and Fittings 26108 -17

Sessions 2 & 3: Bonding Conduit; Metal Conduit Fittings Raceways and Fittings 26108 -17

Objectives When you have completed this session, you should be able to do the

Objectives When you have completed this session, you should be able to do the following: 1. Select and install raceway systems. c. Install metal conduit fittings. d. Make conduit-to-box connections. e. Identify raceway supports. f. Identify installation requirements for various construction methods. Performance Task 1. Identify the appropriate conduit body for a given application. Raceways and Fittings 26108 -17

1. 2. 0– 1. 3. 1 Metal Conduit Fittings • The type of fitting

1. 2. 0– 1. 3. 1 Metal Conduit Fittings • The type of fitting selected depends on the type of conduit, its location, and the installation method. • Couplings are fittings that are threaded inside to join two pieces of conduit. Raceways and Fittings 26108 -17

1. 2. 0– 1. 3. 1 Metal Conduit Couplings are available in various types

1. 2. 0– 1. 3. 1 Metal Conduit Couplings are available in various types for different types of conduit and applications. Raceways and Fittings 26108 -17

1. 3. 2 Insulating Bushings Insulating bushings are used to protect conductors from being

1. 3. 2 Insulating Bushings Insulating bushings are used to protect conductors from being damaged by threaded conduit entering a sheet metal enclosure. Raceways and Fittings 26108 -17

1. 3. 2 Grounding Insulating Bushings Grounded insulating bushings both protect conductors and allow

1. 3. 2 Grounding Insulating Bushings Grounded insulating bushings both protect conductors and allow for the connection of an equipment grounding conductor. Raceways and Fittings 26108 -17

1. 3. 3 Threaded Weatherproof Hubs Threaded waterproof hubs are used for conduit entering

1. 3. 3 Threaded Weatherproof Hubs Threaded waterproof hubs are used for conduit entering a box in a wet location. Raceways and Fittings 26108 -17

1. 3. 4 Offset Nipples Offset nipples are used to make quick offset connections

1. 3. 4 Offset Nipples Offset nipples are used to make quick offset connections between two pieces of equipment in close proximity. Raceways and Fittings 26108 -17

1. 3. 5 Conduit Bodies • Conduit bodies, also called condulets, can be used

1. 3. 5 Conduit Bodies • Conduit bodies, also called condulets, can be used at junctions or pull points. They are more expensive than couplings, but may be required in exposed or outdoor locations or to change the type or size of raceway. • The maximum number of conductors permitted in a conduit body is found using NEC Table 314. 16(B). Raceways and Fittings 26108 -17

1. 3. 5 Type C Conduit Bodies • A Type C conduit body is

1. 3. 5 Type C Conduit Bodies • A Type C conduit body is a straight fitting with a screw-on cover for conductor access. • Type C conduit bodies are used to provide a pull point in a long run or one with bends totaling more than 360°. Raceways and Fittings 26108 -17

1. 3. 5 Type L Conduit Bodies • A Type L conduit body is

1. 3. 5 Type L Conduit Bodies • A Type L conduit body is an elbow fitting that provides a 90° change in direction. • Various types of Type L conduit bodies are available to provide access to the conductors from the top, either side, or both sides. Raceways and Fittings 26108 -17

1. 3. 5 Type T Conduit Bodies Type T conduit bodies provide a junction

1. 3. 5 Type T Conduit Bodies Type T conduit bodies provide a junction point between three intersecting conduits. Raceways and Fittings 26108 -17

1. 3. 5 Type X Conduit Bodies Type X conduit bodies provide a junction

1. 3. 5 Type X Conduit Bodies Type X conduit bodies provide a junction point for four intersecting conduits. Raceways and Fittings 26108 -17

1. 3. 6 Sealing Fittings • A variety of sealing fittings are used in

1. 3. 6 Sealing Fittings • A variety of sealing fittings are used in hazardous location to minimize the passage of dangerous gases and vapors through the conduit system. • Sealing fittings are also used to make connections between hazardous (classified) and nonhazardous (unclassified) locations. Raceways and Fittings 26108 -17

1. 4. 0 Making a Conduit-to-Box Connection Locknuts are used on the inside and

1. 4. 0 Making a Conduit-to-Box Connection Locknuts are used on the inside and outside walls between a box and a conduit connection. A grounding locknut is used for the connection of a bonding wire. Raceways and Fittings 26108 -17

1. 4. 0 Making a Conduit-to-Box Connection • A good conduit-to-box connection requires the

1. 4. 0 Making a Conduit-to-Box Connection • A good conduit-to-box connection requires the use of both internal and external locknuts and a protective bushing. • An offset or kick may be required so that the conduit enters straight into the box. Raceways and Fittings 26108 -17

1. 5. 0– 1. 5. 1 Raceway Supports • Raceway supports must be installed

1. 5. 0– 1. 5. 1 Raceway Supports • Raceway supports must be installed properly into sound structural members. • Straps are often used to support conduit against a surface. Raceways and Fittings 26108 -17

1. 5. 2 Standoff Supports Standoff supports are used to support conduit away from

1. 5. 2 Standoff Supports Standoff supports are used to support conduit away from the structure. Raceways and Fittings 26108 -17

1. 5. 3 Electrical Framing Channels • Electrical framing channels are used with conduit

1. 5. 3 Electrical Framing Channels • Electrical framing channels are used with conduit clamps to support conduit from a ceiling, wall, or other surface. • Trapeze hangers are used with framing channels to support overhead conduit. Raceways and Fittings 26108 -17

1. 5. 4 Beam Clamps Beam clamps are used with suspended hangers. One end

1. 5. 4 Beam Clamps Beam clamps are used with suspended hangers. One end is attached to the beam and the other to a hanger. Raceways and Fittings 26108 -17

1. 6. 0– 1. 6. 1 Identifying Installation Requirements for Various Construction Methods •

1. 6. 0– 1. 6. 1 Identifying Installation Requirements for Various Construction Methods • Raceway installation methods vary by the type of construction. • Concrete boxes are nailed to wooden forms for embedding in the concrete when it is poured. Raceways and Fittings 26108 -17

1. 6. 0– 1. 6. 1 Box with Raised Ring • When installing boxes

1. 6. 0– 1. 6. 1 Box with Raised Ring • When installing boxes flush in masonry construction, the electrician should work closely with the mason laying the blocks. The boxes are made up when the blocks reach the outlet elevation. • Smaller boxes may require extension rings to bring them flush with the masonry surface. Raceways and Fittings 26108 -17

1. 6. 0– 1. 6. 1 Three-Gang Concrete Box Larger boxes do not require

1. 6. 0– 1. 6. 1 Three-Gang Concrete Box Larger boxes do not require extension rings to bring them flush with the masonry surface. Raceways and Fittings 26108 -17

1. 6. 2 Metal Stud Environment • Wiring in a metal stud environment is

1. 6. 2 Metal Stud Environment • Wiring in a metal stud environment is easier than wiring in concrete or masonry. • Metal studs often include pre-punched holes for routing conductors. If not, a hole can be easily punched in the desired location. Raceways and Fittings 26108 -17

1. 6. 2 NM Cable Protected by Grommets NM cable must be protect using

1. 6. 2 NM Cable Protected by Grommets NM cable must be protect using listed bushings or grommets. Raceways and Fittings 26108 -17

1. 6. 3 Wood Frame Environment EMT can be run through wooden members using

1. 6. 3 Wood Frame Environment EMT can be run through wooden members using either notching or boring. Boring is the preferred method. Raceways and Fittings 26108 -17

1. 6. 3 Steel Nail Plate • A nail plate is required to protect

1. 6. 3 Steel Nail Plate • A nail plate is required to protect the conductors where the wiring is installed less than 1¼" from the nearest edge. • Nail plates are also required to protect the conductors in all wooden members. Raceways and Fittings 26108 -17

1. 6. 4 • Conduit can be routed across the structural members that support

1. 6. 4 • Conduit can be routed across the structural members that support the roof in metal building construction so long as it is no less than 1½" away from the roof decking. • The roof structure of a metal building can consist of either beams and purlins or open-web steel joists. Metal Buildings Raceways and Fittings 26108 -17

1. 6. 4 Beam and Purlin Roof System • Beams and purlins should not

1. 6. 4 Beam and Purlin Roof System • Beams and purlins should not be drilled. Instead, the conduit is supported from the metal beams using special anchoring devices. • All conduit is run exposed and must be plumb, level, and neat. Raceways and Fittings 26108 -17

1. 6. 4 Open-Web Steel Joist Roof Supports Raceways and Fittings 26108 -17

1. 6. 4 Open-Web Steel Joist Roof Supports Raceways and Fittings 26108 -17

1. 6. 4 Steel Strut System Rigid metal conduit is often required in steel

1. 6. 4 Steel Strut System Rigid metal conduit is often required in steel building construction. Raceways and Fittings 26108 -17

Next Session… Selecting Fasteners and Anchors for the Installation of Raceway Systems Complete the

Next Session… Selecting Fasteners and Anchors for the Installation of Raceway Systems Complete the 1. 0. 0 Section Review. Read Sections 2. 0. 0– 2. 7. 0 to prepare for the next session. Raceways and Fittings 26108 -17