1. 20CE7020E
BUILDING SERVICES
ELECTRICAL SYSTEMS IN
BUILDINGS
UNIT – 2

2. UNIT 2 ELECTRICAL SYSTEMS IN
BUILDINGS
• Basics of electricity distribution - Earthing systems
and bonding - Electric wiring - Industrial
Installations -Lighting controls - Light sources,
Lamps, Lighting design - Telecommunication
installations.

3. Basics of electricity distribution:
• The basic electrical installations are,
• lighting - providing illumination both inside and
outside buildings
• exhaust fans - providing ventilation both inside
and outside buildings
• use of portable and non-portable electrical
machines or appliances and their wiring
network, including sub-main wiring, cable, O.H.
lines etc, including control panel and switches.

4. BUILDING ELECTRICAL SYSTEM

5. Transmission and distribution
•After electricity has been generated, a system of
electrical wires carries the electricity from the
source of generation to our homes and businesses.
•Transmission lines
, transformers,
substations and
other equipment
have voltages of
100 kV (100,000
volts) and above.

6. Types of Electric Power Distribution Systems
1) According to the nature of the supply
• AC Distribution system
• DC Distribution system
2) According to a type of connection
• Radial system
• Ring system
• Interconnected system
3) According to a type of construction
• Overhead system
• Underground system

7. Classification According to Nature of
Supply
Primary distribution system
Secondary distribution system
AC Distribution system
AC voltage can be easily step up and step down with
the help of a transformer.

8. primary distribution system
It is used to convert 11
kV to 415 V. And this
power is directly
distributed to the small
consumers.

9. Secondary distribution system
generated AC power is
converted into DC power with
the help of a rectifier or rotary
converter. The applications
where we need DC power are;
traction purpose, DC motors,
Battery charging, and
electroplating.

10. DC Distribution System
•The load is connected in parallel between two lines. Generally,
the load connected in this system is lamp-load or motors. The
load has only two terminals can be connected in this type of
system.

11. DC Distribution System
• Three-wire DC distribution system
Hence, the load requires a higher
voltage that is connected
between healthy wires, and the
load requires a lower voltage
that is connected between one
healthy wire and a neutral wire.

12. Classification According to Method of
Connection

13. Radial System

14. Ring Main System

15. Radial, Loop, & Network Systems:
Radial
Loop
Network

16. Power Distribution System
• It receives High volt power from a transmission network
then stepped down it by a step-down transformer to the
primary distribution level voltage. Primary distribution
voltage is usually 11 kV, but can range between 2.4 kV to 33
kV depending upon region or consumer.

17. Earthing systems and bonding:

19. Earthing
• earthing is to limit the duration of touch
voltages if you were to make contact
with an exposed conductive part. The
earth creates a safe route for the current
to flow instead of causing electric shock.

20. Bonding
•The purpose of bonding is to reduce the risk of electric
shock if you find yourself touching separate metallic parts
when there is a fault somewhere within the electrical
installation. Protective bonding conductors reduce the
magnitude of touch voltage in this scenario.

21. TN-S System

22. TN-C-S
System

23. TT
System

24. Electric wiring
• Electrical wiring is an electrical installation of
cabling and associated devices such as
switches, distribution boards, sockets, and
light fittings in a structure.

25. Non-Metallic (NM) Sheathed Cable:
• Most interior wiring is done with non-metallic,
or NM, cable—also known by the popular
brand name Romex.
• NM cable is made of three or more wires
wrapped inside a flexible plastic jacket, or
sheathing. It is used for most interior circuits,
such as those for outlets, switches, light
fixtures, and appliances.

26. Direct-Burial Cable
• Standard electrical cable is designed to be
run indoors, where it stays dry and is
protected by wall, ceiling, or floor
structures.
wires are embedded in solid vinyl to fully protect them
from moisture.

27. Different Types of Electrical Wire
• NM Cable
• UF Cable
• THHN
• THWN
• Low-Voltage Wire
• Phone and Data Wire
• Coaxial Cable

28. NM cable (Non metallic cable)
• White sheathing - NM cable with 14-gauge conductors.
• Yellow sheathing - NM cable with 12-gauge conductors.
• Orange sheathing - NM cable with 10-gauge conductors.
• Black-sheathed - for both 6- and 8-gauge wire.

29. UF Cable
It is commonly used for supplying outdoor
fixtures, such as lampposts.
Like standard NM cable, UF contains insulated
hot and neutral wires, plus a bare copper
ground wire.

30. THHN and THWN wires
• They have colored sheathings used to
identify their function in a circuit:
• Hot wires: Black, red, orange
• Neutral wires: White, brown
• Ground wires: Green, yellow-green

31. Low-Voltage Wire
• Low-voltage wiring is used for circuits typically
requiring 50 volts or less.
• Several common types are landscape lighting
wire, sprinkler system connections, bell wire
(for doorbells), speaker system wires, and
thermostat wires.

32. Phone and Data wire
• Telephone and data wiring are low-voltage wires
used for “landline” telephones and internet
hookups, typically made from copper.
• Telephone cables may contain four or eight wires.
• It can be used for both phone and data
transmission and offers greater capacity and
quality than standard phone wire.

33. Coaxial cable
• Coaxial cable used in connecting televisions to
antenna or cable service delivery and is still
often used to connect satellite dishes or to
bring subscription television service to an in-
home distribution point.
• It typically has black or white insulation and is
perfectly round in shape

34. Industrial installations
• Its a network of wires connecting various
accessories for distribution of electrical energy
from the supplier meter board to the
numerous electrical energy consuming devices
such as lamps, fans and other domestic
appliances through controlling and safety
devices is known as a wiring system.
Electrical Wiring & Installation

37. Tree System

38. Joint Box System
Methods of Wiring:

39. Loop System
This system is universally used for connections of
various lamps or other appliances in parallel.
The phase or line
conductors are looped
either in switch board or
box and neutrals are
looped either in switch
board or from light or fan.
Line or phase should
never be looped from
light or fan.

40. Different Types of Electrical Wiring
Systems
The types of internal wiring usually used are
• Cleat wiring
• Wooden casing and capping wiring
• CTS or TRS or PVC sheath wiring
• Lead sheathed or metal sheathed wiring
• Conduit wiring

41. Cleat Wiring
• This system of wiring comprises of ordinary VIR
or PVC insulated wires (occasionally, sheathed
and weather proof cable)
• Cleat wiring system is a temporary wiring
system therefore it is not suitable for domestic
premises.
• The use of cleat wiring system is over
nowadays.

42. Wooden casing and capping wiring
• The cable used in this type of wiring is
either VIR or PVC or any other approved
insulated cables.

43. Battern (CTS or TRS or PVC sheath) wiring
• In this type of wiring the cables used may be single core,
twin core or three core TRS cables with a circular oval
shape. Usually single core cables are preferred.
• TRS cables are sufficiently chemical proof, water proof,
steam proof but are slightly affected by lubricating oils.

44. Lead Sheathed Wiring
• The type of wiring employs conductors that are
insulated with VIR and covered with an outer sheath of
lead aluminum alloy containing about 95% of lead.
• The metal sheath given protection to cables from
mechanical damage, moisture and atmospheric
corrosion.
• This types used for Low voltage Applications

45. Conduit Wiring
In this system of wiring steel tubes, known as conduits,
are installed on the surface of walls by means of saddles
or pipe hooks or buried under plaster and VIR or PVC
cables are drawn into afterwards by means of a GI wire
of size of about 18 SWG.

46. Lighting controls
• Lighting controls are a range of smart
lighting devices that can regulate the
levels, quality and characteristics of light in
a defined space.
• These smart devices aid in reducing
electricity wastage while simultaneously
encouraging energy efficiency.

47. They switch on the lights automatically as they detect
motion and turn them off when the area is not occupied
for a certain amount of time.
For instance, Savvy is a range of smart PIR
occupancy sensors by Wipro Lighting that uses advanced
passive infrared technology for detecting patterns and
ranges.
1. Occupancy Sensors
Lighting controls

48. A dimmer allows the users to control and alter the
“intensity of illumination” as per their preferences. It
encourages convenience as users can lighten or darken the
room with simple controls
2. Dimmers
Lighting controls

49. Integrated lighting controls permit the users to alter the
lighting scenes in a defined space. They allow the users to
modify and set a lighting scene that comprehends their
mood. Various LED lighting manufacturers offer IoT-enabled
control systems that allow users to control lighting with
mobile phones and other internet-enabled devices.
3. Integrated Lighting Controls
Lighting controls

50. Light sources, Lamps, Lighting Design
• Lighting Design: Location of Light Sources:
Light plays an important role in the perception of the
environment around us, without light there is no vision and
vision gives us a part of our sensory experiences. Despite the
charm, daylighting persists in some defects such as glare, heat
penetration, discoloration of furniture and fabric dyes, etc.
hence the need for artificial lighting. A basic understanding of
the colour, intensity, and texture of light supports the ideas
which will undermine a project’s design goals. Refining
layouts, materials, and scale can’t make a huge difference that
light can quickly and powerfully alter the appearance and
emotional effect with a few simple strokes. For every space
design decision, there needs to be a complementary lighting
decision.

51. Light sources, Lamps, Lighting Design
• Light from the Ceiling onto Walls

52. Light sources, Lamps, Lighting Design
• Lighting from the Ground

53. Light sources, Lamps, Lighting Design
• Lighting from the Wall Upwards

54. Light sources, Lamps, Lighting Design
• Lighting the Wall

55. Light sources, Lamps, Lighting Design
• Light from Slots and Coves

56. Light sources, Lamps, Lighting Design
• Low Lighting onto the Floor

57. Light sources, Lamps, Lighting Design
• Suspended Glowing Sources

58. Telecommunication installation
• Telecommunications are the means of electronic
transmission of information over distances. The
information may be in the form of voice
telephone calls, data, text, images, or video.
• Today, telecommunications are used to organize
more or less remote computer systems into
telecommunications networks. These networks
themselves are run by computers.
• A telecommunications network is an arrangement
of computing and telecommunications resources
for communication of information between
distant locations.

59. Telecommunication installation