1.
Types and Installation of Metal Conduits, Wires, and Cables
Types of Metal Conduits
1. Rigid Metal Conduit (RMC)
o Made from galvanized steel or aluminum.
o Thick walls provide excellent protection.
o Typically used in outdoor or industrial settings.
2. Intermediate Metal Conduit (IMC)
o Thinner and lighter than RMC but strong and durable.
o Ideal for exposed applications.
3. Electrical Metallic Tubing (EMT)
o Lightweight and thin-walled.
o Used in indoor applications.
o Often referred to as "thin-wall conduit."
4. Flexible Metal Conduit (FMC)
o Corrugated, flexible metal tubing.
o Ideal for areas with tight bends or vibration.
5. Liquid-Tight Flexible Metal Conduit (LFMC)
o Similar to FMC but with a waterproof plastic covering.
o Used in wet or corrosive environments.
6. Aluminum Conduit
o Lightweight and resistant to corrosion.
o Suitable for areas where steel might corrode.
Installation of Metal Conduits
Plan the layout and measure conduit lengths.
Cut the conduit with a pipe cutter or hacksaw.
Deburr the cut edges for smoothness.
Use conduit connectors and couplings to join sections.
Secure the conduit using straps or hangers (spacing per code).
Pull wires through the conduit using fish tape or a pull line.
Ground the conduit system as per electrical codes.
Types of Wires and Cables
1. Non-Metallic Sheathed Cable (NM)
o Common in residential wiring.
2. Armored Cable (AC) or Metal-Clad Cable (MC)
o Enclosed in a metal sheath for extra protection.
3. Underground Feeder (UF) Cable
o Designed for direct burial underground.
4. Thermoplastic High-Heat-Resistant Nylon-Coated Wire (THHN)
o Common in commercial wiring.
5. Coaxial Cable
o For cable TV or internet installations.
6. Control Cables
o Used in industrial applications for controlling systems.
Installation of Wires and Cables
Verify the appropriate type and size for the circuit.
Route wires and cables through conduits or spaces per code.
Secure cables using clamps or staples without damaging insulation.
Maintain proper separation from heat sources and sharp edges.
Follow color-coding conventions for easy identification.
2. Types and Installation of Boxes, Fittings, and Multi-Outlet Assemblies
Types of Electrical Boxes
1. Standard Rectangular Box
o For switches and single outlets.
2. Square Box
o For junctions or multiple outlets/switches.
3. Octagon Box
o For ceiling fixtures like lights or fans.
4. Round Box
o For ceiling fixtures or smoke detectors.
5. Weatherproof Box
o Used outdoors with a watertight seal.
Types of Fittings
1. Couplings
o Connect two sections of conduit.
2. Connectors
o Attach conduit to boxes or enclosures.
3. Bushings
o Protect wires from sharp conduit edges.
4. Locknuts
o Secure conduits or connectors to boxes.
Types of Multi-Outlet Assemblies
1. Raceways
o Surface-mounted channels with multiple outlets.
2. Power Strips
o Multi-outlet extensions for temporary use.
3. Multi-Gang Boxes
o Contain multiple switches or outlets in one box.
Installation of Boxes, Fittings, and Multi-Outlet Assemblies
1. Installation of Boxes
o Mount boxes securely to studs or masonry using screws or brackets.
o Ensure box size complies with electrical codes for wire capacity.
o Position boxes flush with wall surfaces for proper cover plate fit.
2. Installation of Fittings
o Use appropriate fittings for conduit type (threaded or clamp-type).
o Tighten connections to ensure a secure fit and proper grounding.
3. Installation of Multi-Outlet Assemblies
o Plan the layout and mark positions on walls or surfaces.
o Mount assemblies using screws or adhesive strips.
o Connect wiring according to circuit requirements and secure outlets/switches in
place.
o Install covers to protect and enhance the appearance.
