BEEE NOTES.pdf

Notes about a wiring

1. BASICS OF HOUSE
WIRING AND IT'S TOOLS

2. THE MAINS ELECTRIC SUPPLY TO YOUR HOUSE:
• The main electric supply to any house comprises a three-core wiring
system – the live, neutral and earth
• The brown or red active (live) wire brings in the current, blue neutral
wire takes current back and the green, or yellow, earth wire is joined
to a metal plate installed deep within the earth
• Electricity is supplied to circuits of 15amp for appliances of high
power rating and 5amp for those with low power rating

3. INSULATED WIRES, A MUST
• Insulating wires is an important preventive hence using insulating wires
like Heat Resistant Wire (HR), Fire Resistant Wire (FR) & Low Smoke Wires
(FRLS) help to withstand fires & prevent other electric hazards.
•Insulated wire or cable consists of a non-conductive material
resistant to an electric current. It surrounds and protects the
wire or cable inside.
•The obvious benefit of insulated wire is the color. While this may
seem simple, it’s very important, especially in sophisticated wire and
cable applications. Colored insulation can help you determine the
difference between wires when there are many running together.

4. THE RIGHT WIRE FOR THE RIGHT USE:
• The selection of wires must be compatible with the power
usage of an appliance
• Wires are made of copper or aluminium, and are a se
conductor of electricity
• A wire can be solid or stranded
• A solid wire is appropriate for higher frequencies
• Stranded wires are used for flexibility

5. BASIC HOUSE WIRING
INSULATING WIRE

6. •Once the power reaches the house via the service drop or
service lateral cables, it passes through the electric meter, which
may be mounted on an exterior wall or may be located inside the
home's breaker box.
•The meter records all electricity used by the home, measured in
kilowatt-hours, or kWh. A 100-watt light bulb burning for 10 hours
uses 1 kWh of electricity. Meters may be analog or digital type,
although most new meters are digital and can be read remotely
by the utility company.
TOOLS AND COMPONENTS
ELECTRIC METER:

7. ELECTRICAL BOXES:
•An electrical box is a plastic or metal box used to connect wires and
install devices such as switches, receptacles (outlets), and fixtures. An
electrical box is almost always required for mounting devices and for
housing wiring splice
•Boxes come in many different sizes and several different shapes. A
box must be sized appropriately for the number and size of wires
entering the box. Metal electrical boxes must be grounded to the
home's grounding system; plastic boxes do not need grounding
because they are nonconductive.

8. HOT AND NEUTRAL WIRES:
•Each electrical circuit contains at least one "hot" wire that carries
the electrical current from the service panel to the circuit devices
and a neutral wire that carries current back to the service panel.
•Hot wires typically are black or red but can be other colors.
Neutral wires typically are white. In some circuits, the neutral wire
is used as a hot wire and the circuit has no dedicated neutral.

9. ELECTRIC METER

10. CABLE
•Cables are made up of conducting materials like copper or
aluminium that surrounded by insulation and sheath giving a
mechanical protection.
•Insulation is provided on the conducting material to block the
path of leakage current from the con ductor, thus minimizing
the risk of shock and fire.

11. FLEXIBLE CORDS
•Flexible cords consist of a large number of fine wires to form the
conducti These are insulated by plastic insulation. These are used as
connecting wires for connections to portable domestic appliances
and light fittings such as table fa radio, ceiling rose, etc.
•The flexible cords connected to portable appliances incorporate an
earth continuity conductor. When these are used in suspending
pendant lighting fittings, the maximum weight of the fittings should
be such that cord can safely permit it without any breakage.

12. ELECTRIC FUSE
•In electronics and electrical engineering, a fuse is an electrical
safety device that operates to provide overcurrent protection of an
electrical circuit.
•Its essential component is a metal wire or strip that melts when too
much current flows through it, thereby stopping or interrupting the
current.

13. PLUGS AND SOCKETS
• AC power plugs and sockets connect electric equipment to the
alternating current (AC) mains electricity power supply in buildings
and at other sites.
• Electrical plugs and sockets differ from one another in voltage and
current rating, shape, size, and connector type. Different standard
systems of plugs and sockets are used around the world