Chapter 10 Raceway Systems Objectives Become familiar with

Chapter 10 Raceway Systems

Objectives • Become familiar with the many different types of raceway systems. • Understand the distinct uses of different types of raceways, based on the NEC. • Cut, prepare, and join various types of raceway materials. • Practice essential conduit bending techniques. Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Raceway and Conduit • Raceway – Enclosed channel housing wires, cables, or busbars • Conduit – Tubing or channel connecting boxes Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Electrical Metallic Tubing (EMT) • Rigid conduit of galvanized steel • Connected with setscrew and compression couplings • Equipment grounding conductor Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

EMT Connections Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Cutting Metal Conduit • Hacksaw, reciprocating saw, pipe cutter Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Reaming Metal Conduit • Remove burr after cutting with deburring tool or files – Burrs can damage insulation Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Safety Note • Metal shavings can cause serious eye damage • Always wear safety glasses when working with metal materials • Best habit is to wear protection at all times on jobsite Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Bending Metal Conduit • Field bend made on construction site • Conduit bender • Know minimum bend radius allowed by Code Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Offset Bend • Goes around obstruction or change in plane • Opposing bends that change conduit elevation • Shrink is shortening conduit due to bends Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Offset Bend Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Stub Bend • 90° bend up or down to a box Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Back-to-Back Bend • Two 90° bends • Ends of conduit pointing in same direction Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Box Offset • Two 5° bends align conduit with knockout hole Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Saddle Bend • • Two 22 ½ bends and one 45 bend Around obstruction and returns to same elevation Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Electrical Nonmetallic Tubing (ENT) • Flexible corrugated plastic – “Smurf tube” or “smurf” • Connects with snap fittings or bonding cement • Buried in concrete, behind walls • Cannot be buried in soil or left exposed Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Electrical Nonmetallic Tubing (ENT) Goodheart-Willcox Publisher; Carlon, Lamson & Sessions Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Rigid Metal Conduit (RMC) • Galvanized, smooth surfaces – “Heavy-wall conduit” • Connections with threaded fittings • Serves as equipment grounding conductor • Mast heads and exposed installations Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

RMC Connectors and Fittings Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Code Alert RMC Bushings Section 344. 46 • Bushings to be used where rigid metal conduit enters a box, fitting, or other enclosure to protect wire from abrasion Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Intermediate Metal Conduit (IMC) • Heavy-duty, rigid conduit • All atmospheric conditions and occupancies • Joined with threaded fittings • Can serve as equipment ground Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Rigid PVC Conduit (PVC) • Nonconductive polyvinyl chloride (PVC) plastic • Lighter and easier to work than metal conduit • Connect to metallic and nonmetallic boxes and conduit • Heat to bend Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Joining Rigid PVC Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Flexible Metal Conduit (FMC) • Spiral-wrapped metal conduit – Greenfield • Special couplings, locknuts, and bushings • Bends in EMT or rigid conduit Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Code Alert Grounding and Bonding FMC Section 348. 60 • Grounding and bonding requirements for FMC • Grounding conductor must be used where vibration or flexibility • Used as equipment grounding conductor in accordance with Section 250. 118(5) Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Liquidtight Flexible Metal Conduit • Flexible steel or aluminum conduit • Plastic sheath makes it watertight Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Surface-Mount Raceway • System of hollow tracks or channels, boxes, fittings – Base and cover • Mounts to wall or ceiling • Electrical wiring and data cables • Dry locations not subject to damage Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.