- Single phase power uses a single conductor to transmit power while three phase uses three conductors and a neutral. - Three phase power is preferable for larger loads and industrial applications due to benefits like constant power delivery and self starting induction motors. - To change from single phase to three phase, a certified electrical contractor submits an application to the electricity provider and completes installation works before testing and commissioning.

2. SINGLE PHASE
THREE PHASE Wires

3. ALTERNATING
CURRENT
THREE
PHASE
SINGLE
PHASE

4. ALTERNATING CURRENT
GENERATED IN POWER
PLANTS
CURRENT CHANGES DIRECTION AS IT
GOES THROUGH DIFFERENT
TRANSFORMERS.
FUNCTION:
FOR ELECTRICITY
TRANSMISSION AND
DISTRIBUTION.
TRANSFORMER – DEVICE WITH MUTUALLY
INDUCTIVE COILS USED TO CONVEY AC
POWER FROM ONE COIL TO ANOTHER.
40/60
DUP

5. SINGLE PHASE
In single phase circuit, there will be only one phase.
the current will flow through only one wire and there will be one
return.
THREE PHASE
Act as a three phase system.
the current will flow through three wires and there will be one
return.

6. SINGLE PHASE
Commonly found in domestic households.
Follow British standard voltage: 230 V
THREE PHASE
Preferable for larger homes, industrial, office
or business.
Standard Voltage: 415 V
APPLICATION

7. ADVANTAGES DISADVANTAGES
Single Phase
Simple, no complex installation procedures, thus lower labor fees, quick
Installation
Lower current tolerance (electrical tripoff may occur more frequently when overusage of
electricity)
Cheaper distribution system (smaller motor & component size) High insulation costs
Less substations required Not uniform torque
Lightweight, compact unit
Three Phase
Cost saving over a long run Share a common core
Constant power delivery High repair cost
Self starting induction motors Transformer capacity reduced
Less conductor material Unbalanced loading
Rotating magnetic field Complex system

8. SINGLE PHASE THREE PHASE
Definition The power supply through one conductor. The power supply through three conductors.
Wave shape
Number of wire Require two wires for completing the circuit (one phase and one neutral) Require three phase wires and one neutral wire for completing the circuit.
Voltage It carries voltage up to 230v It carries voltage up to 415v
Fault occur
Since it has only one phase wire, and it the fault occurs on the network, then
power supply completely fails
Since it has three phases, and if the fault occurs on any one of the phases, the other two
will continuously supply the power
Maintenance Require more maintenance and become costly Require less maintenance
Uses Mostly used in the house and for running the small loads Mostly used in large industries and for running heavy loads.
COMPARISON

9. ENERGY METER
A device that measures the average energy
(kWh) by loads.
ELECTRICAL BUS BAR
A conductor used for collecting electric power
from the incoming feeders and distributes
them to the outgoing feeder.
CONSUMERS
MOLDED CIRCUIT BREAKERS
Protects an electrical circuit from over current
or overheating.

10. Live Wires
Neutral Wires
Electric Meter
Main MCCB
Sub Panel
Devices
THREE PHASE SUPPLY LEGEND
SECTION – three PHASE SUPPLY DIAGRAM

11. ENERGY METER
A device that measures the average energy (kWh)
by loads.
MINIATURE CIRCUIT
BREAKERS AND BUS
BARS
For LOW VOLTAGE
NETWORKS

12. Plug/Device
Neutral Wire
Live Wire
Electric Meter
Switch Box
SINGLE PHASE SUPPLY LEGEND
3D SINGLE PHASE SUPPLY
DIAGRAM
PLAN VIEW OF SINGLE PHASE
SUPPLY DIAGRAM

13. HOW TO KNOW WHEN TO CHANGE FROM SINGLE
PHASE TO THREE PHASE?
Usage of electricity exceeds 50
amps or 10 Kw.
Circuit breaker constantly tripping.
Multiple high electrical current items (air-
conditioner, water heater, etc) running at the
same time.

14. STEPS OF CHANGING SINGLE
PHASE TO THREE PHASE

15. 1APPLICANT
• Submit application online via myTNB service portal
• Appoint an certified electrical contractor to submit on their
behalf
• Settle connection charges billed by TNB
• Once installation is complete
1. Deposit a sum of money
2. Make an appointment with TNB for meter installation
3. Sign electricity supply contract with TNB

16. 2CERTIFIED ELECTRIC CONTRACTOR
• Submit the application form on behalf of the applicant
• Settle connection charges upon approval of the applIcation by TNB
• Before implementing the electricity installation works (As
according to Electricity Regulations 1994):
1. Sub regulation 12(1) and 12(2), upon completion of installation,
wireman shall certify a supervision and completion certificate
2. Sub regulation 13(1) and 13(2), Wireman need to certify the Test
Certificate for the installation
3. Sub regulation 14(1), Both certificate shall be in Forms G and H as
prescribed in the First Schedule.
• Make an appointment with the TNB on behalf of the applicant to sign
the electricity supply contract

17. CASE STUDY
Location: 25, Jalan PJS 7/6, Bandar
Sunway, 47500 Subang Jaya, Selangor
Type of building: 2 storey terraced
house
SINGLE PHASE WIRING

18. DISTRIBUTION BOARD SINGLE PHASE METER BOX

19. REFRIGERATOR
(1 UNIT)
WATER HEATER
(4 UNITS)
AIR-CONDITIONER
(7 UNITS)

20. REASON FOR INSTALLING SINGLE-PHASE
• It is more widely available in residential setting and is less expensice to purchase.
• It is more preferable for small terrace house and where the requirement of power is
less.
• It is also relatively cheaper as it has a smaller motor and component size.
• It is also easy to install with simple installation processes. (compared to three phase)

21. CASE STUDY
Name of PROject: Ascot Hill, Bukit Rahman Putra
Location: 2, JLN BRP 2/1J, BKT RAHMAN PUTRA,
47000 SG BULOH.
Type of Building: 3- storey Semi- Detached
Courtyard House
Rooms: 5 Bedrooms + 4 Bathrooms
Developer: Sabna Development Sdn. Bhd
Mechanical& Electrical Engineer:
EAB Consulting Engineer Sdn Bhd
THREE PHASE WIRING

22. DISTRIBUTION BOARD 3 PHASE METER BOX

23. REFRIGERATOR
(1 UNIT)
WATER HEATER
(4 UNITS)
AIR-CONDITIONER
(7 UNITS)

24. REASON FOR INSTALLING 3-PHASE
• High electricity usage as there’s 3 storey, which means more equipment needed power supply.
• Having 3-phase allow to split the electricity usage for example first phase is for lighting and fans
etc; second phase is for TV, refrigerator and others. Third phase is for AC, Inverter system etc…
• More wiring is needed to connect all the rooms
• When a circuit breaker of a circuit or distribution board trip due to some reason, then all bulb
and loads would not disconnect at once.

25. COSTING
APPROACH

26. LICENSE APPLICATION
EXTERNAL and INTERNAL WIRING + LABOUR
A HIGHER one shot payment is needed to be made when applying for a 3-Phase Wiring
System than a Single-Phase Wiring System
3-Phase Wiring System has THREE active wires and ONE neutral wire (more wires required)
thus, a HIGHER material cost.
Internal wiring is required to DISTRIBUTE the current provided by the AC source and external
wiring throughout the building.
Skilled Labor is also needed to fix up this wiring system as it is more COMPLICATED than the
Single-Phase Wiring System, thus increase in labor cost.
MAINTAINING FEES
LOWER cost in long term as 3-Phase wiring has a longer lifespan & the chances of
breakdown is lower compared to single phase

27. The tariff from TNB is the SAME whether you use single-phase
or three-phase power.
Three-phase wiring has a HIGHER ELECTRICAL SUPPLY but as
long as you have the same number of appliances and the same
usage time, the electricity bill will stay the same.
HOW ABOUT THE ELECTRICITY BILL??