Objectives 1. To understand the placement of of arrangement sequence sequence of parts in a Consumer box 2. To interpret a schematic schematic diagram of a Consumer box into a complete wiring wiring diagram. 3. To install a complete complete wiring of a Consumer 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
KWH meter
Main Fuse Switch
ELCB
Lamp circuit
Fan circuit
Functional
Malfunction
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 1.0 conductor size as for it could hold 10 amp of current which means it’s maximum power of up to 2400 watt
