House wiring is the web used to power your homes, which is often invisible but essential. They are always hidden behind walls and ceilings. By understanding the house wiring system, you can do proper planning and installation if you’re building a new home or updating an older one.
Read this blog to understand more about house wiring, its components, the National Electrical Code, and more.
What is Home Electrical Wiring in India?
House wiring is the process of installing electrical cables, switches, sockets, and other fixtures for a residential building, adhering to Indian safety regulations. For effective house construction, you need to consider the house’s electrical wiring according to the wiring diagram for future comfort and energy efficiency.
What is a Wiring Diagram?
The visual representation of your house building’s circuits and electrical properties is called a wiring diagram or electrical drawing. It contains lines and symbols in a layout that describes the electrical system of the property. An electrical engineer will generally design this.
Basic Components of Home Electrical System
A well-designed electrical system will generally include the following basic components:
Main Service Panel
An electrical panel is the focal point of electricity distribution. It is commonly called the main distribution board (MDB). It obtains electricity from the grid and safely sends it to all the circuits in buildings. If there is a short circuit or overload, it protects the electrical system.
The electrical supply for homes in India is generally delivered from the local grid at a standard voltage of 220V with a frequency of 50Hz.
Circuit Breaker Systems
You can consider a circuit breaker system as a protective component of the electrical panel. The circuit breaker system includes Miniature Circuit Breakers (MCBs) and Residual Current Circuit Breakers (RCCBs).
MCBs are used to protect electrical circuits from damage caused by overcurrent, short circuits, or overloads. It automatically shuts off the electrical flow when it detects excess current, preventing the circuit from overheating and driving to fire or other hazards.
RCCBs prevent electric shock and fire hazards by spontaneously disconnecting the electrical circuit when they detect an imbalance in the electric current flow.
The combination of these devices improves the safety of the electrical system by ensuring an immediate response to electrical faults.
Switches, Sockets, and Load Devices
Electrical wiring in-house, including switches and socket outlets, is used to control the power supply for appliances and lighting. The common types of switches used in Indian homes are modular and toggle switches; they are convenient and simple to use. The type of appliances and electronic devices indicates the load on the electrical system. For the electrical safety of the house, make sure that the load on the system does not exceed the capacity of the circuit breakers.
Earthing Systems
To eliminate electrical faults, you need to provide a safe path for excess electricity. By including earthing systems, you can reduce the risk of electric shocks and damage to pricey equipment. In India, different types of earthing methods are used; common methods are plate earthing, pipe earthing, and chemical earthing.
Electrical Wire and Electrical Cables
An electrical wire is a single conductor that carries electricity. The electrical cable is a bundle of two or more wires in a single jacket. Wires are the individual insulated or bare conductors inside the jacket.
You need to understand different types of electrical wires and their functions to ensure safety and compliance in electrical installations. In India, the Bureau of Indian Standards (BIS) sets guidelines for wire colours and safety practices to reduce the risk of electrical accidents.
The following are three types of wires:
1. Hot Wires
Hot wires often carry live current from the electrical panel to the required destination area. These wires will be clearly marked in 4 colours:
- Black Wires: Black wires always indicate a hot wire in Indian electrical systems. They transport power from the service panel (breaker box) to various electrical devices.
- Red Wires: Red wires will be used as secondary hot wires. They are typically used in applications where a separate switch controls a device, such as in ceiling fan installations.
- Blue & Yellow Wires: Blue and yellow wires can be used as hot wires in certain applications. Blue wires are commonly used for travellers in three-way and four-way switch applications.
2. Neutral Wires
Neutral wires carry power back to the service panel and are critical for completing the electrical circuit. Although they are classified as neutral, they may still carry current and should be handled with caution.
- White & Gray Wires: White and grey wires indicate neutral wires in electrical systems. They pose a risk of electrocution if improperly handled, as they can still carry current under certain conditions.
- White Wires with Black or Red Tape: Wires that are white with black or red tape should be treated as hot wires and must not be confused with standard neutral wires. Proper identification is crucial for safety during installation and maintenance.
3. Ground Wires
Ground wires are important to give a safe path for electrical current in case of faults in the electrical system.
- Green Wires: Green-coloured wires are often used for grounding purposes in India. They connect all electrical devices to the ground. Ground screws on electrical devices are often painted green, signifying their role in safety.
- Bare Copper Wires: Bare copper wires are also utilised for grounding and provide an effective path for electrical faults to dissipate safely into the ground.
Electrical Cable Types
Electric cables are classified into different types based on their voltage ratings. This will help to determine their suitable applications and construction standards. They are all designed and made according to standards to ensure safety and reliability.
Low Voltage Cables (up to 750 V)
Low-voltage cables are utilised in a variety of applications; they commonly include thermoplastic or thermoset coatings.
Low Voltage Cables (up to 1,000 V)
These cables are also referred to as 0.6/1 kV cables. These cables are commonly used for industrial power installations across various sectors, including general industry, public installations, and infrastructure projects. They are manufactured in compliance with international standards for higher safety.
Medium Voltage Cables (1 kV to 36 kV)
These cables are used to distribute electricity from electrical substations to transformer stations. Their capacity to handle higher voltages makes them essential for efficient power distribution.
High Voltage Cables (from 36 kV)
High-voltage cables are used to transport electricity from generating plants to electrical substations. These cables are designed to handle significantly higher voltages, making them vital for long-distance electricity transmission.
Understanding Modern Wiring Standards
In India, the National Electrical Code (NEC) provides important guidelines for safe electrical installations. The Bureau of Indian Standards (BIS) has given standard regulations, like IS 732, to guide the design and safety of wiring. These rules help prevent electrical hazards. Following these standards, regular maintenance and appropriate installation of wiring are important for staying safe. Many electrical accidents happen due to faulty wiring or overloaded circuits, so following safety guidelines is very important.
Best Positions of Electrical Outlets within Your House
You need to consider the most appropriate positioning of electrical outlets with the help of electric layouts. The position of outlets ensures convenience and avoids overloading circuits. The following are some general guidelines for outlet placement in different rooms within a house:
Kitchen: You can place multiple outlets near the countertops and use separate circuits for big appliances like refrigerators and microwaves.
Living Room: Locate outlets behind TVs and large furniture, or make use of false ceilings. Have at least one outlet every 12 feet.
Bedrooms: Locate outlets close to beds and dressers so you can easily plug in chargers and lamps when it’s required.
Bathrooms: Use special GFCI (Ground Fault Circuit Interrupter) outlets close to sinks, but keep them away from water to prevent shocks.
Outdoor Areas: Always choose outlets that are weatherproof, including covers to protect them from moisture and dust.
The Cost of Electrical Wiring in a New House
The cost of electrical installation in a new house is not just about the cost of wires. Along with the wire costs, you need to consider labour costs, which can vary based on the number of electricians required and the total number of days needed. And the cost of other accessories like metal boxes, switches, conduit pipes, etc. In India, the electrical wiring cost per square foot can range from INR 100 to INR 250.
However, you can consult a professional to get the right cost estimate.
Common Household Electrical Wiring Issues
Circuit Breaker Problems
Circuit breakers break to prevent fires from overloads. But if yours breaks often, even with a few appliances running, there may be a wiring issue or ground fault. Call an electrician to check.
Power Surges, Sags, or Dips
- Surges: Sudden power spikes can cause damage to electronics. Use surge protectors and call an electrician if surges happen often.
- Sags/Dips: These cause dimming lights and happen due to faulty outlets or outdated panels.
Dead or Few Outlets
Too few outlets lead to overload. Dead outlets are not at all safe and should be replaced with the help of an electrician.
You can work with an experienced electrical engineer or construction company to do your house electrical wiring installation. If you like to do it yourself, you must follow the standard regulations of the Bureau of Indian Standards (BIS). Specific electrical works, such as adding new circuits or major rewiring, demand approval from local authorities. Without the proper permits, you can face legal problems if something goes wrong. It’s always best to hire an experienced electrician.
Hemali Patel