Question

State different types of holders used in wiring installation.

Answer 1

1. Direct Fasteners (for Securing Cables to Surfaces)

These are used to attach individual or small groups of cables directly to building structures like studs, joists, or walls.

• Cable Staples:
  Description: U-shaped fasteners, typically made of metal or plastic. Metal staples are often insulated (coated in plastic) to prevent damage to the cable's sheathing.
  Use: The most common method for securing non-metallic sheathed cable (e.g., Romex®) to wood studs and joists during residential rough-in wiring. There are specific staples for different types of cables (low voltage, coaxial, etc.).

• Cable Clips / Saddles:
  Description: Small plastic or metal clips, often with an integrated nail or screw. They come in round or flat profiles to match the cable shape.
  Use: Securing individual, smaller cables like coaxial (TV), Ethernet (data), telephone, or bell wire to surfaces like baseboards, walls, and joists. They provide a neater appearance than staples.

• Cable Straps:
  Description: Strips of metal or plastic with one or two holes for screws or nails. They are more robust than staples.
  Use: Used for securing larger cables, armored cables (like MC or BX), or conduits to surfaces. One-hole straps are common for conduit, while two-hole straps provide stronger support.

2. Bundling and Organizing Devices

These are used to group multiple wires together for better organization and management.

• Cable Ties (Zip Ties):
  Description: Self-locking plastic strips, typically made of nylon. They come in various lengths, strengths, and colors.
  Use: Primarily for bundling and organizing loose wires inside enclosures, along cable trays, or in low-voltage applications (like data networking). Note: In many jurisdictions, standard zip ties are not code-compliant for supporting permanent mains voltage wiring from a building structure.

• P-Clamps (Adel Clamps):
  Description: A band of metal or plastic with a rubber or vinyl cushion, shaped like the letter 'P'. A screw or bolt passes through the two ends to secure it.
  Use: Provides a very secure, vibration-resistant mounting for cables, harnesses, or conduits, especially in automotive, aviation, and industrial applications.

3. Conduit, Raceways, and Trays (for Protection and Routing)

These holders enclose wires completely, offering physical protection and a clear pathway.

• Conduit:
  Description: A tube or pipe used to protect and route electrical wiring. It is held in place by straps.
  Types & Use:

  *   **EMT (Electrical Metallic Tubing):** Lightweight steel tubing used for indoor commercial and industrial applications.
  *   **PVC (Polyvinyl Chloride):** Plastic conduit used in corrosive or wet environments and for underground burial.
  *   **Rigid Metal Conduit (RMC):** Heavy-duty galvanized steel conduit that provides the highest level of physical protection.
  *   **Flexible Metal Conduit (FMC) & Liquid-tight FMC (LFMC):** Used for connecting to equipment that may vibrate or move, like motors.
  

• Surface Raceway (Trunking):
  Description: A plastic or metal channel with a snap-on cover that mounts directly onto a wall's surface.
  Use: Used to run wires in existing buildings where it's impractical to run them inside the walls. Common in offices for data cables or adding outlets to solid walls (brick, concrete).

• Cable Trays:
  Description: An open support system, typically a ladder-like or ventilated trough made of steel or aluminum.
  Use: Used in industrial and commercial buildings to support large quantities of power and data cables over long distances, often suspended from the ceiling.

4. Support for Suspended Cabling

These are used in commercial buildings, data centers, and industrial sites to support cables running overhead.

• J-Hooks:
  Description: J-shaped metal or plastic hooks that provide a wide, smooth support base for cables.
  Use: Primarily for supporting low-voltage, data, and fiber optic cables to prevent kinking or damage that can affect performance. They are attached to ceilings, beams, or walls.

• Bridle Rings:
  Description: Simple, open metal rings with a threaded end for screwing into building structures or fasteners.
  Use: An inexpensive way to support low-voltage and data cables. They allow cables to be easily added or removed.

5. Enclosures and Boxes (for Connections and Terminations)

While their primary purpose is to enclose connections, these boxes are also critical "holders" of the wiring system.

• Junction Boxes:
  Description: Metal or plastic boxes that house and protect wire splices and connections.
  Use: To safely contain connections where wires are joined together. They must remain accessible after installation.

• Device Boxes (Switch/Outlet Boxes):
  Description: Boxes designed to hold devices like switches, outlets, or dimmers.
  Use: They secure the device and hold the ends of the cables connecting to it. They are mounted on or in walls, floors, or ceilings.

• Cable Glands / Connectors:
  Description: Fittings used to attach and secure the end of a cable to equipment or an enclosure.
  Use: They provide strain relief for the cable and can also provide a seal to protect against dust, water, or hazardous gases. They "hold" the cable as it enters a box or panel.

Choosing the right holder depends on the type of cable, the environment (indoor/outdoor, wet/dry), the surface material (wood, metal, concrete), and, most importantly, the requirements of the local electrical code.

Answer 2

1. Pendent Holder
2. Batten Holder
3. Angle holder
4. Screwed holder