Objectives
1. To understand the placement of arrangement sequence of parts in a
Consumer box
2. To interpret a schematic diagram of a Consumer box into a complete wiring
diagram.
3. To install a complete wiring of a Consumer Box from supply source to a load
point.
4. To test the ELCB operational.
5. Obey the IEE and JBE regulation.
Tools
Tools
Side cutter
Tack hammer
Combination pliers
Test pen
Screw driver
Multimeter
Introduction
A consumer unit is a type of distribution board (a component of an electrical
power system within which an electrical power feed provides supply to subsidiary
circuits).
Procedures
1. Interpret the schematic diagram into a complete wiring diagram.
2. Connect all parts in the consumer box as the arrangement sequence.
3. Connect a lamp load or a fan load point as the load circuit from a circuit
breaker/fuse point in the consumer box.
After finish wiring installation
4. Do the physical test on wiring installation.
5. Connect 240V supply source to the consumer box using an extension cord
and operate wiring installation.
Parts
Functional
Malfunction
KWH meter
Main Fuse
Switch
ELCB
Lamp
circuit
Fan circuit

x

x

x

x

x
Result
COFFIN
ELCB
EARTH
LIVE
NEUTRAL
1. COFFIN - breaks when a fault occurs
2. ELCB -A safety device that trips and disconnects power when there's a
leakage of current to earth on any of the circuits it protects.
3. EARTH
4. LIVE
5. NEUTRAL
Discussion
While installing our consumer box, we accidently connected a wrong wire cable
which resulting our consumer box to not functioning properly. We noticed this fault
when Mr. Kamal tested our consumer box with multimeter. Both red and black cable
responded when it touches the negative and positive of the multimeter. When both of
the wire responded, this means that our circuit is short. After a guide from Mr. Kamal,
we manage to overcome the problem.
Conclusion
Throughout the experiment, we as a new student had been taught installation about
consumer box. We learn a lot of new things such as: how to install the consumer
box, how to fix the live, and earth and neutral wire by following the label on the
socket. We also enjoyed did this experiment. We are also exposed to some
information about proper testing by using ammeter. After that we are also able to test
the success of the installation by using 240V power socket .Finally we are able to
install the consumer box successfully, when the light turn on.
Question
1. What are the functions of the consumer box?
2. What is a circuit breaker/fuse current rate value for lamp load and fan load circuits?
3. State the most suitable cable size for lamp load and fan load circuit.
Answer
1. Function of consumer box:
 distributes electricity to the final circuits
 contains switches which allow the supply to each individual circuit to be
switched off
 contains devices which protect the occupants from electric shock and the
wiring and appliances from damage
2. A mechanical switching device, capable of making, carrying and breaking
currents under normal circuit conditions. Also capable of making and carrying
for a specified time and breaking currents under specified abnormal circuit
conditions, such as those of a short circuit.
3. The most suitable cable size for lamp load and fan load is 1.0mm2 conductor
size as for it could hold 10 amp of current which means it’s maximum power
of up to 2400 watt