Another crucial item required during construction of your house and also as a first step of finishing works are electric wires. Electric wires serve the purpose of supplying current to all your appliances and devices. Electric wire consists of two components, copper conductor and insulation. Copper conductor is the main component that carries current whereas insulation carries the copper conductor in it.
Electric wires used in houses are also known as “General Purpose” wires. This type of wires are manufactured in different sizes and cores however following are only required during house construction:
Single Core 3/.029 or 1.5 mm
Most of the wires used in a residential house are single core 3/.029. Where 3 indicates number of copper conductors inside the insulation and .029 indicates diameter in inches of each conductor. 3/.029 wire is used to supply current to all low voltage appliances and devices.
Single Core 7/.029 or 2.5 mm
7/.029 is the wire that is used as main wires of each room separately where 7 indicates number of copper conductors inside the insulation and .029 indicates diameter in inches of each conductor. A single 7/.029 wire connects respective room with the main DB (Distribution box) hence carrying all load of that particular room excluding air conditioner or any other high current appliance/device that is wired completely separately.
Single Core 7/.036 or 4 mm
Every house consists of many high current appliances such as Air conditioners, electric heaters, electric geezers, ovens etc. Though all these wires can operate on 3/.029 or 7/.029 too, preferred wire for such appliances and devices is 7/.036 electric wires where 7 indicates number of copper conductors inside the insulation and .036 indicates diameter in inches of each conductor.
4 Core 19/.052 or 25mm
A very critical wire used in house construction is 4 core 19/.052 where 19 represents number of strands/conductors in each core and .052 indicates effective cross-section of each core. These wires are used as main wires that connect the main electric supply from high voltage wires to your house. 4 core wires are available both in Copper strands and silver strands, the main supply high voltage wires fixed by the government are made of silver, however it is always recommended to used copper 4 core wires for main connection since it carries all the electric load of a house.
Intercom/telephone cable 1 to 5 pair
All companies manufacturing general cable electric wires for residential or commercial purpose, also make communication cables used for intercoms, telephones and other low voltage devices. These wires are manufactured in different pairs where each pair consists of two separate strands/conductors. 1 pair is generally used throughout the house for telephone connections. Whereas 5 pair is used from Main entrance of house to internal junction box of communication services for connecting intercom, camera, electric locks etc.
Coaxial cable RJ-6/RJ-7
Another important cable that is required nowadays in houses is Coaxial cable that comes in two grades named as RJ-6 or RJ-7 where 6 represents superior quality of signal transmission. Coaxial cables are used for networking, communication dishes, television connections, long range CCTVs etc. Separate conduit/pipes are fixed in walls for coaxial cable where ever connection is required in house for TV/Dish.
There are many brands manufacturing quality general purpose electric wires that claim there wires to be 99% copper and fire proof insulator. Some of them are:
- Pakistan cables
- Fast cables
- FR cables
- GM cables
- Excel cables
Quality check on site for electric wires
Though they might or might not have a conductor that comprises of 99.9% copper, however all these brands are highly recommended. A small fire test can be carried out to test the insulator of wires on site. Take a small piece of wire and light a fire on it, the insulator should not act as a fuel and enhance the fire, it should resist and extinguish the fire quickly. Quality of insulator depends upon the rate at which fire extinguishes. Better the quality, more quickly the fire will extinguish. Secondly copper quality can easily be checked on site by its permanent and ineradicable colour, can be bent and twisted without breaking or stretching. There are many nameless wires available in the market at cheap rates, however most of such wires are of inferior quality. Using such wires in houses or other places is never recommended. Inferior quality wires can cause short circuits resulting in fires and utility bills for electricity consumption can also be on higher sides.