ELECTRICAL WIRING
CIRCUITS, LIGHTING
SCHEME AND BELL
CIRCUITS
Prepared by Ms. Shirley Nangami
,Distribution of Electrical Energy
There are two methods of distribution of electrical energy beyond energy meter in the domesti
and power installation:
1. Distribution board system
2. The tree system
Distribution Board System:
This method is a common system adopted by
consumers of domestic installations. The fuses of
various sub- circuit are grouped together at a place
close to the main switch known as the distribution
board.
One wire is taken from bus bar through a fuse and
neutral is taken from a neutral link. The pair of wires
(phase and neutral) taken from main distribution
boards is fed to a final sub-circuit board.
Fig 1 - Electrical energy distribution (dist
system)
,Distribution of Electrical Energy
The Tree System
In this system, smaller branches are taken from the main
branch. A fuse is inserted at the commencement of each
branch. It has the following disadvantages:
Voltage across all the lamps doesn't remain the same.
The lamp in the last branch will have less voltage
across them due to voltage drop in the leads.
A number of joints are involved in every circuit.
The fuses are not at one place.
Fault location is difficult. If a fault occurs, all the
joints in the wiring will be inspected thoroughly to
locate the fault.
Fig 2: Electrical energy distribution (Tre
, Wiring systems
It is a net work connecting various accessories for distribution of electrical energy from the supp
numerous electrical energy consuming devices and equipment.
It is an assembly of parts used in the formation of one or more electric circuits. Wiring cons
conductor with its protection against mechanical damage (sheathing and/or armoring) and certa
accessories for fixing the system, and joining and terminating the conductors.
The most commonly employed wiring systems are:-
1. Cleat wiring
2. Sheathed cables wiring
3. All insulated cables wiring
4. Catenaries wiring
5. Conduit system
6. Trunking system
CIRCUITS, LIGHTING
SCHEME AND BELL
CIRCUITS
Prepared by Ms. Shirley Nangami
,Distribution of Electrical Energy
There are two methods of distribution of electrical energy beyond energy meter in the domesti
and power installation:
1. Distribution board system
2. The tree system
Distribution Board System:
This method is a common system adopted by
consumers of domestic installations. The fuses of
various sub- circuit are grouped together at a place
close to the main switch known as the distribution
board.
One wire is taken from bus bar through a fuse and
neutral is taken from a neutral link. The pair of wires
(phase and neutral) taken from main distribution
boards is fed to a final sub-circuit board.
Fig 1 - Electrical energy distribution (dist
system)
,Distribution of Electrical Energy
The Tree System
In this system, smaller branches are taken from the main
branch. A fuse is inserted at the commencement of each
branch. It has the following disadvantages:
Voltage across all the lamps doesn't remain the same.
The lamp in the last branch will have less voltage
across them due to voltage drop in the leads.
A number of joints are involved in every circuit.
The fuses are not at one place.
Fault location is difficult. If a fault occurs, all the
joints in the wiring will be inspected thoroughly to
locate the fault.
Fig 2: Electrical energy distribution (Tre
, Wiring systems
It is a net work connecting various accessories for distribution of electrical energy from the supp
numerous electrical energy consuming devices and equipment.
It is an assembly of parts used in the formation of one or more electric circuits. Wiring cons
conductor with its protection against mechanical damage (sheathing and/or armoring) and certa
accessories for fixing the system, and joining and terminating the conductors.
The most commonly employed wiring systems are:-
1. Cleat wiring
2. Sheathed cables wiring
3. All insulated cables wiring
4. Catenaries wiring
5. Conduit system
6. Trunking system
