Electrical wiring is the distribution of electrical energy through wires in a perfect manner. It is for the economical use of wiring conductors inside, and outside of a room or building with better load control.
Electrical Energy Distribution Systems
Following the ISI’s recommendations, the maximum number of points of lights, fans, and socket outlets cannot exceed 10. Loads up to 800 watts can be connected to such a circuit. Hence, in case of more load or more points to be connected to the supply the system, then it is to be done by having more than one circuit through a
- Joint Box or Jointing system
- Loop-in or Looping system
Joint Box system
With the joint box wiring system, the cable from the consumer unit runs to a series of joint boxes. Where a joint box system is specified, all joints are made using approved mechanical connectors in suitable and approved joint boxes.
Advantages of Joint Box wiring
- Less expensive as it does not use long-run cables, and wiring can be saved.
- Joint box connections are more reliable and safer.
Disadvantages of Joint Box wiring
Whenever a fuse blows, all other appliances in that joint box get disconnected.
Loop-in wiring system
Loop-in wiring system is the most universally used wiring practice, also sometimes called a looping system. The most common wiring type in houses is the loop-in system because it is the most economical. The wiring is done without any junction boxes or connection boxes.
Advantages of Loop-in method of wiring
- Most economical type of wiring in houses.
- As this is a parallel connection system each appliance can be controlled individually.
- This system does not use a joint box, so money can be saved.
Disadvantage of the Loop-in method of wiring
- More cable run lengths are required.
Classification of Electrical Wiring System
The electrical wiring system is classified into four categories.
- Cleat wiring
- Enclosure wiring or Casing and Capping wiring
- Batten wiring
- Conduit wiring
1. Cleat Electrical wiring
VIR or PVC insulated wires are braided and blended into the walls or ceiling using porcelain cleats in this wiring. Wires can be weatherproof. Simple wire laying is done in this wiring system. Nowadays, this type of wiring is not recommended for homes or buildings.
This wiring is used only in temporary army campuses or festival-related functions. As shown in the above figure, porcelain or plastic studs having two or three groves are used to lay cables.
Advantages of Cleat wiring
This type of wiring has certain advantages
- Easy and inexpensive wiring.
- Easy fault detection.
- Easy to repair.
- Laying of wiring and further addition and modifications are easy.
Disadvantages of Cleat wiring
The disadvantages of this wiring are
- This type of wiring is not used in permanent setups.
- As wiring is temporary, not attractive appearance.
- Exposed to the weather being affected by humidity, rain, smoke, sun, etc.
- Risk of shock or fire.
- Suitable for the low ambient temperature of 220 volts.
- Not long-lasting.
2. Enclosure wiring or Casing and Capping Electrical Wiring
Enclosure wiring is also called casing and capping wiring. It is a rectangular-shaped enclosure, available with grooved compartments. Generally, used in rooms to lay short-length data cables, fiber optic, and telecommunications. Also, PVC or VIR insulated wires are routed through the enclosure, and a plastic or wooden cover is used to cover the enclosure.
Advantages of enclosure-type wiring
This type of wiring has the following advantages.
- Inexpensive and easy to install.
- A strong and durable wiring system.
- Modification can be done easily.
- Protected from smoke, dust, rain, steam, etc.
- Due to the envelope and the closure, no risk of shock.
Disadvantages of enclosure wiring
Enclosure wiring has some drawbacks, they are
- Not suitable for very humid and acidic weather conditions.
- Possibility of damage to the frame and wood covering by insects such as termites.
- The risk of fire cannot be overruled.
3. Batten Electrical Wiring
Straight teak wooden slats are used to lay single, double, and triple conductor cables. The cables are retained using a tin-plated brass clip or loop clamp. Brass pins are used to secure the loop fasteners to the wooden slat. Loop clips are attached to wooden slats at intervals of 10 cm for horizontal runs and 15 cm for vertical runs with brass pins.
Advantages of Batten wiring
The advantages of this type of wiring are
- Easy to set up.
- Cost-effective in terms of material.
- Heavy cables can not be used.
- The wiring appearance looks attractive. Its orderly appearance is clean and creates a visually pleasing environment.
- A simple method of personalization, and easy.
- Less risk of leakage of current.
Disadvantages of Batten wiring
- This kind of wiring is not suitable for outdoor, open-area wiring.
- Environmental conditions such as humidity, smoke, steam, etc. directly affect the wires.
- Wires of heavy sizes are not recommended for batten wiring systems.
- Only for voltages less than 220 volts.
- As wires are side by side, the risk of fire is high.
4. Conduit wiring
An electrical conduit protects and provides a route for the wiring in a system. There are rigid and flexible electrical conduits made of metal, plastic, or fiber. Wiring of this type is not easy to install. GI wire is used to lay the wires through the conduit pipe. The size of industrial metal conduit available in the market is 19, 20, 25, 32, and 40mm.
Conduit system can be classified according to their wall thickness, mechanical stiffness, and the material from which it is made. Material selection is based on mechanical protection, corrosion resistance, and installation cost (labor and material cost).
Both metallic and non-metallic conduits are used as per requirement.
Metal conduits include a rigid metal conduit (RMC), galvanized rigid conduit (GRC), Intermediate metal conduit (IMC), and electrical metal conduit (EMT).
The most common type of non-metallic conduit is PVC conduit. PVC is popular due to its lightweight in comparison with metal conduit. PVC conduit is preferred because it is usually more affordable.
Two classes of metal conduit for electrical wiring are recognized as standard A) Plain B) Threaded.
Class A conduit
consists of light gauge conduits of thicknesses. The ends of the conduit are plain.
Class B conduit
consists of heavy gauge conduit of the thickness. The ends are threaded.
Concealed Conduit wiring
Concealed wiring is sometimes referred to as concealed conduit wiring. The arrangement of this wiring is made under the plaster of the wall or the building. Under the plaster of the wall, conduits are buried with a GI wire inside.
Then, using GI wires, the main PVC insulated cables are pulled through the conduit. It is very laborious to install.
Surface conduit wiring
As can be seen in the image, the surface conduit is laid on the wall surface. It is both in metallic and non-metallic (PVC) tubes. Metal conduits are generally GI material. The main advantage of surface conduit wiring is that large wire pairs can be added and larger conductors can be upgraded.
Advantages of Conduit wiring
The main advantages are
- The safest wiring.
- Appearance is better.
- Wiring through conduit pipes does not have the risk of fire.
- No risk of damage to cable insulation.
- Keep away from moisture, smoke, steam, etc.
- No risk of shock.
- Conduit wiring is long-lasting.
Disadvantages of conduit wiring
- Compared to any other type of wiring, it is very expensive.
- Conduit cost is naturally high.
- Installation is not easy.
- It is not easy to modify in the future.
- It is difficult to detect faults.