The benefits of proper electrical wiring in a building cannot be overemphasized, as it is the energy framework of any building or structure. Almost every appliance used in our homes and businesses require electricity to function and the bedrock of energy use and flow in a building is a measure of how efficiently the wiring installation was carried out.
There are 3 common methods of wiring n Nigeria- Surface wiring, Conduit wiring and Trunking. We’ll be discussing Conduit wiring as it is the safest and most popular.
Wiring a building by conduit is carried out in 3 major steps:
Preparing the conduit channels.
Laying the conduit framework.
Running the wires.
PREAMBLES:
Before you begin any wiring installation, it is important to have an electrical drawing (sometimes called an M&E drawing). This is an architectural sketch of the different fittings and socket points, with the wire framework a building will have based on its intended function. A professional electrician or architect can help you with this all-important document.
PREPARING THE CONDUIT CHANNELS: This is often done before or during foundation-laying stage of the building. It involves digging trenches and paths to carry the conduit pipes based on the electrical drawing. A common practice is to trace from the planned power source and dig from there.
Materials required include:
Drills
Mattock for digging
Hacksaw or other cutting tools, etc
LAYING THE CONDUIT FRAMEWORK: This is done when the concrete work is semi-completed so as to reduce the time and effort spent in digging fully dry concrete. It involves laying the PVC or metal conduit pipes into the trenches dug earlier. Also, laying pipes within the walls in the building to carry wires for the building’s interior.
Materials required include:
PVC or metal pipes (bendable types are most ideal)
Piping accessories like couplers and male bush (used for combining pipes)
U, Y and 4-way boxes
Handsaw and other piping accessories, screws, etc
RUNNING THE WIRES: At this stage, the wires are fit into the conduit pipes along the piping framework and ended at prescribed circuit points. The wires to be used are aligned together in live, neutral and earth according to specified colour codes. Then using a fishing tape/hook, the wires are pulled through the conduit from end to end.
Materials required include:
Pure copper wires in live, earth and neutral. (Copper is the best conductor for electricity)
Fishing hook
Copper or plastic knockout boxes to mark points for fitting
A distribution board or unit connecting all the circuits in the building
Other wiring accessories
EARTHING:
This is often treated as a last resort in building wiring but I believe otherwise because an unearthed or improperly earthed building (or equipment or system) is very dangerous and a disaster waiting to happen. Earthing simply means connecting a building or system or equipment with the earth’s electric charge to protect against electric surges or prevent fire outbreaks in the event of a lightning strike.
Materials for earthing include:
Earth rod (pure copper please)
Arrestor/earth mat
Earthing tape
Earth salt and other accessories.
Please consult with an electrical professional before installing any of the above, as specified by national and global laws on electrical handling.