Module 3 : Wiring Methods in Electrical Systems

Open Wiring on Insulators

Exposed wiring using cleats and knobs.

Concealed Knob-and-Tube

Wiring method using knobs and tubes, concealed.

Type AC Cable

Flexible metal enclosure for insulated conductors.

Metal-Clad Cable (Type MC)

Insulated conductors in a metallic sheath.

Armored Cable (Type AC)

Fabricated assembly of insulated conductors, flexible.

Direct Burial

Cable installation underground, identified for use.

Cable Tray

Support system for multiple cables in one area.

Aerial Cable

Cable suspended on a messenger wire.

Services, Feeders, Branch Circuits

Electrical distribution components in wiring systems.

Power Circuits

Circuits designed to supply electrical power.

Lighting Circuits

Circuits specifically for lighting fixtures.

Control Circuits

Circuits for controlling electrical devices.

Signal Circuits

Circuits for transmitting signals or communications.

Exposed Wiring

Wiring not concealed within building structures.

Concealed Wiring

Wiring hidden within walls or ceilings.

Corrosive Vapors

Harmful gases that can damage wiring materials.

Damp Locations

Areas with moisture but not wet conditions.

Wet Locations

Areas subject to direct water exposure.

Hazardous Locations

Areas with potential fire or explosion risks.

Flexible Tubing

Protective covering for insulated conductors.

Insulated Conductors

Wires coated to prevent electrical contact.

Nominal Voltage

Standard voltage level, typically 600 volts.

Masonry Walls

Walls made of brick or stone materials.

Moisture-Impervious Jacket

Protective layer preventing moisture ingress.

Metallic Sheathing

Metal covering providing physical protection to cables.

Knobs and Tubes

Traditional wiring method using ceramic knobs.

Fish Cable

Running cable through walls or ceilings.

Type NM Cable

Not for multifamily dwellings over three floors.

Type NMC Cable

Prohibited in hazardous classified locations.

Type NMS Cable

Not allowed in places of assembly.

Type MC Cable

Avoid in corrosive conditions like direct burial.

Type MI Cable

Mineral-insulated, metal-sheathed cable for various uses.

Type SNM Cable

Shielded nonmetallic-sheathed cable for moisture resistance.

Service Entrance Cable

Single or multi-conductor for service applications.

Type SE Cable

Flame-retardant, moisture-resistant service entrance cable.

Type USE Cable

Permitted for service laterals above ground.

Type TC Cable

Used for power, lighting, and control circuits.

Type UF Cable

Underground feeder and branch circuit cables.

Type FC Cable

Flat cable assemblies for direct burial.

Corrosive Conditions

Includes exposure to strong chlorides and caustic alkalis.

Mineral Insulation

Highly-compressed refractory mineral for conductor insulation.

Liquidtight Sheath

Gastight covering for Type MI cable.

Moisture Resistance

Protection against water and humidity exposure.

Flame Resistance

Material that resists ignition and burning.

Exposed Locations

Areas where cables are not concealed or protected.

Concealed Locations

Cables installed within walls or ceilings.

Direct Burial

Cables installed underground without additional protection.

Branch Circuits

Circuits that extend from a distribution panel.

Power Circuits

Circuits designed to deliver electrical power.

Signal Circuits

Circuits used for communication signals.

Cable Trays

Support structures for multiple cable runs.

Raceways

Enclosed channels for electrical wiring.

Physical Damage

Damage from external forces affecting cable integrity.

Type UF Cables

Permitted for underground and interior wiring.

Type FCC Cables

Flat copper conductors for branch circuits.

Type TC Cables

Factory assembly of insulated conductors.

Nonmetallic Extensions

Insulated conductors in nonmetallic jackets.

Integrated Gas Spacer Cable

Aerial cable with supporting messenger integrated.

Medium Voltage Cable

Rated 2001 volts or higher for power systems.

Flat Conductor Cable

Three or more flat conductors placed edge-to-edge.

Overcurrent Protection

Protection against exceeding rated ampacity.

Cable Trays

Supports multiple conductors in a single assembly.

Messenger-Supported Wiring

Wiring supported by a messenger wire.

Direct Burial

Installation of cables directly in the ground.

Service Entrance Cables

Cables used for electrical service entry.

Hazardous Locations

Areas requiring special wiring considerations.

Corrosive Vapors

Gases that can damage electrical components.

Raceway

Enclosed channel for wires and cables.

Branch Circuit

Circuit that supplies power to outlets.

General Purpose Circuit

Circuit for general electrical use.

Appliance Branch Circuit

Circuit dedicated to specific appliances.

Aerial Cable

Cable installed above ground, often supported.

Loose-Fit Nonmetallic Conduit

Flexible conduit for insulated conductors.

Directly Buried Cables

Cables installed without additional protective covering.

Voltage Rating

Maximum voltage a cable can safely carry.

Corrosive Locations

Areas where materials can corrode wiring.

Surface Extensions

Wiring extensions mounted directly on surfaces.

Twisted Conductors

Conductors twisted together for stability.

Factory-assembled Wiring

Wiring pre-assembled in a factory setting.

Multi-Conductor Type

Cable with multiple conductors in one assembly.

Cable Assemblies

Combination of multiple cables into one unit.

Intermediate Metal Conduit (IMC)

Metal raceway with circular cross-section for conductors.

Rigid Metal Conduit (RMC)

Specially constructed raceway for electrical conductor installation.

Flexible Metallic Tubing (FMT)

Non-rigid conduit for drawing conductors post-installation.

Electrical Metallic Tubing (EMT)

Thinner-walled metal conduit for concealed or exposed work.

Rigid Nonmetallic Conduit

Nonmetallic conduit resistant to moisture and chemicals.

Surface Metal Raceway (SMR)

Metal assembly for surface mounting of electrical conductors.

Liquidtight Flexible Metal Conduit

Flexible metal raceway with liquidtight outer jacket.

Surface Nonmetallic Raceway

Nonmetallic raceway for surface mounting, moisture-resistant.

Busway

Assembled metal trough for bare conductors as feeders.

Underfloor Raceway

Raceway type suitable for installation under flooring.

Cable Tray

Structural system used to support electrical cables.

Cable Bus

Assembly of insulated conductors in ventilated metal housing.

Cellular Floor Raceway

Enclosed metal housing with hollow spaces for conductors.

Multi-outlet Assembly

Surface flush raceway for conductors and receptacles.

Messenger Wire

Support wire for insulated conductors in installations.

Corrosion Protection

Measures to protect conduits from corrosive environments.

Dissimilar Metals

Avoid contact to prevent galvanic corrosion in systems.

Enamel Protection

Corrosion protection using enamel for ferrous raceways.

Hazardous Locations

Areas requiring special conduit types for safety.