Wiring Regulations and Installation

Wiring Regulations

• Electrical wiring demands expert attention for all building projects, directly impacting human safety and equipment handling.
• Wiring scope encompasses supply, installation, testing, and commissioning of conduits, accessories, wiring, switches, outlets, junction boxes, pull boxes, and connections.

Wiring Materials and Installation

• Electrical wiring needs expert attention, directly related to human safety and building utility/equipment safety.
• Scope includes supply, installation, testing, commissioning of all conduits, accessories, wiring, switches, socket outlets, spur outlets, junction boxes/pull boxes, GI pull wires, ceiling roses, and connections.

Conduit Wiring and Installation Methods

• Conduit wiring uses tubes (steel or PVC) for mechanical and fire protection of conductors.
• Conduit pipes can be installed on walls/roofs (using saddles/hooks) or concealed within walls/roofs/floors.
• Modern construction utilizes PVC or GI conduit, with installation types varying based on site requirements and specifications. These are surface/open and recessed/concealed.

Why Use Conduit Wiring

• When starting wiring projects, deciding on the right type is crucial.
• Some wiring has a sheath coating requiring only stapling to wall studs and joists.
• Conduit is a common choice.

Protecting Wires from Damage

• Conduits vary in strength (from fairly strong to extremely rigid) to prevent damage during installation and use.
• Choosing the correct conduit type is essential, satisfying project needs and complying with the National Electrical Code.

PVC Conduit

• Commonly used in underground and wet locations.
• Features PVC fittings, connectors, couplings, and elbows, easily attached with a cleaner and PVC glue.
• PVC is non-conductive, requiring proper grounding methods at connection points using a green ground wire.

Flexible Metal Conduit

• Ideal for areas requiring tight bends and close quarters (e.g., water heaters, can lights, attic vents).
• Typically used for installations with frequent bends and limited space.

Electrical Metallic Tubing (EMT)

• Lightweight, easily bent, used within walls.
• Easily damaged unlike IMC or RMC/RSC.

Intermediate Metallic Conduit (IMC)

• Thicker, galvanized conduit, making it suitable for outdoor installations, exposed walls (basements, garages), or areas prone to damage.

Rigid Metal Conduit

• Thickest and heaviest conduit, suitable for extreme conditions (e.g., under driveways, service feeder installations).
• More expensive, frequently used for service entrance piping due to its strength and durability that can withstand wind, falling branches, and storm damage.

Electrical Wiring Systems and Methods

• Electrical wiring installations must comply with regulations and standards.
• Incorrect installations can damage devices and result in reduced device lifespan.
• Factors like building construction type, ceiling/wall/floor construction, and installation requirements influence wiring choices.

Individual Conductor Systems

• Open wiring on insulators: Suitable for temporary wiring, offering protection through flexible mica tubing, porcelain tubing, and cleats, especially beneficial when making bends and connecting wires.

Concealed Wiring

• Concealed wiring resembles open wiring, but conductors are hidden within walls or ceilings.

Raceway Systems

• Flexible metal conduits: Used instead of rigid conduits when needing numerous bends.
• Underfloor raceways: Commonly found in fire-resistant buildings, provide an enclosed conduit system beneath the flooring.
• Cellular metal raceways: Used with cellular steel floors, preventing larger conductors from disrupting the system.
• Wireways: Offer convenient metal raceways for conductors up to 500,000 circular mils.
• Busways: Often used in industrial plants due to adaptability for future expansions and modifications of production lines.
• Surface metal raceways: Commonly used in buildings for additional outlets in areas where concealing conduits is more challenging using a metal molding.

Other Systems

• Non-metallic conduit (PVC): Suitable for industrial environments with corrosive liquids, simplifying conduit layouts when encountering obstructions.
• Cable assembly system:
• Service entrance cable: Armored or non-metallic sheathed cables for service entrance purposes only.
• Non-metallic waterproof wiring: Used in cold storage and wet locations where corrosive fumes and vapors are present.
• Non-metallic extensions: Used for adding additional outlets from existing ones.
• Underplaster extensions: Used to expand existing branch circuits by creating additional outlets.