The International Electrotechnical Commission ( IEC ) is the international organisation that sets standards for all electrical, electronic and related technologies. These standards cover the entire gamut of electricity from generation, transmission to distribution. It also covers standards adopted for appliances, gadgets, equipments, machinery etc.
Every country use different standards in electrical voltage, frequency, plugs, sockets, lighting etc. But many countries either group together or use largely common standards. It goes without saying that the lack of standardisation across the nations in the world in terms of voltage and receptacles – entails many extra costs for manufacturers and also puts pressure on the environment.
In India the standard residential Single Phase Electricity supply voltage is 220 V ( AC ) at 50 Hz Frequency. The standard Three Phase Electricity supply Voltage is 415 V ( AC ). A combination of Type C, D and M receptacle types ( Plugs & Sockets ) are prevalent in India.
An Electrical Utility is the Electric Power Supply Company and in the Indian context are mostly public utilities. It engages in all aspects of electricity supply which is mainly the electricity distribution. Many times they even handle generation and transmission. The Electrical Utility is indispensable nowadays and when they cease to function – it plunges not only our lives into disarray but also reduces industrial and even agricultural output.
The electricity utilities fix the tariff structure and is divided into classes of services or sectors like – residential, agricultural, commercial, industrial etc. They also do the task of metering and collecting the amount for the electricity consumption from consumers, apart from developing and maintaining the utility systems and networks.
Electrical Wiring refers to the laying of electrical conductors to carry electricity to safely run the devices that operate on electricity.
Color codes and standards are adopted to prevent confusion and make connections easy and safer. In all electrical installations – color coding is mandatory – though many local and country specific codes do exist.
In India the color codes are : the Three Phase wires are to be in RED, YELLOW and BLUE. The Neutral wire is to be in BLACK and the Earth ( Ground ) wire is to be in GREEN.
Electrical Wiring methods vary depending on the intended use (residential, agricultural, commercial, industrial etc ) and the amount of electricity to be carried by the system ( loading pattern ) and the type of occupancy and size of the building, apart from the national regulations and the environmental considerations.
Electrical wiring systems in a small house is relatively simpler, compared to the extensive wiring required for a large industrial or commercial establishment, where owing to the large amount of current carried and the larger number of machinery, equipment apart from lighting and other fixtures – the electrical wiring needs are more complex.
The maximum standard current loading in your home in the Indian context is 15 Amps per Phase – so for a Three Phase connection the maximum current loading possible is 3 X 15 Amps = 45 Amps. For Industrial, Commercial or Agricultural needs – where heavier loads are to be used – specific approvals for maximum loads have to be obtained from the Electrical utility.
Electrical wires and cables are rated by the circuit voltage, current to be carried and other environmental conditions, such as presence of gaseous inflammable fumes, temperature etc.
Your home electrical wiring starts with your electrical service connection provided by the electrical utility. This is where the electrical service company connects to your home feeder electrical wiring system and as a standard system protocol, the electrical energy measuring meter is the point where the electrical utility connects with your home electrical system. This meter monitors and records all the consumption of electrical energy in your home electrical system and based on the recordings herein – the electrical utility bills you for the electricity consumption on a cyclical basis – which is mostly monthly or bimonthly.
After the electricity Energy Meter, the Mains Switch is positioned and this has a Fuse built-in. The main switch allows to cut out the supply into your home during maintenance or in the event of an emergency. Nowadays all homes are connected with Three Phase Supply and in the Indian context this consists of three separate Phases ( Red, Yellow and Blue wires ) along with Neutral ( Black ) and Earth ( Green ) or Ground. The electrical service connection is to be located outside your home – that is the energy meter and mains switch have to be accessible from outside of your home.
The next important component in the home wiring system is the Distribution Board or Panel. This panel is generally located within your home and houses the Tripper Switches or the Circuit Breakers. The Three incoming Phases are distributed in your home as different electrical circuits after segregation based on load types – depending mainly on the current consumption.
Ideally loads / electrical points with low consumption ( like Light / Fan etc ) are bunched together and so is the case with Medium loads ( Refrigerator / Kitchen appliance etc ) and Heavy loads ( AC / Geyser etc ). Tripper / Circuit breakers are of Appropriate rating ( 4 / 10 / 20 Amps ) for Low / Medium / Heavy loads respectively.
The control of each electrical circuit is done by Tripper Switches or Circuit Breakers. They help to break the electrical circuits in the event of overloading and earth leakage, electrical shock or short-circuit. There is generally a 3 Pole master Tripper or Circuit breaker for all the Three Phases combined to cut out the supply to the entire Distribution Panel in emergencies. Care should be taken to size the Tripper Switches and Wires appropriately based on loading pattern in each electrical circuit.
Ensuring that the Switches, Sockets and Plugs are sized properly - according to the load requirement of the light fitting, appliance or gadget that is to be connected, helps greatly in their trouble-free operation.