1. A Presentation on
OPTIC FIBRE CABLE
BY
Dhruv Infratel PVT LTD
Telecom Training Centre
(ISO 9001:2000 Certified)
Delhi-100075
Email – Info@dhruvinfratel.com

2. OPTIC FIBRE CABLE

3. Objectives
• What is OFC?
• OFC Advantages
• OFC Types & Applications
• Specifications
• Future Trends
• OFC Installation
• Pulling Method with Nylon rope
• Blowing Method

4. Limitations of copper
network
•Copper is costlier and
scarce material.
•Fault prone.
•Maintenance difficult
•Vulnerable for EMI.
•Installation time consuming.

5. Limitations of copper based
network
•Expansions make
congestions in MDF
•B/W LIMITED.
•Loop Resistance
restricts the length of
operation.

6. What is OFC ?
Fibre Optic cable functions as a
“LIGHT GUIDE”, guiding the light
introduced at one end of the cable
through to the other end.

7. Advantages of Optic Fibre
• More Bandwidth - Thousands of Channels
• Low Loss - 0.5db per km
• Less number of Repeaters
• Electro Magnetic Immunity
• Small size & Light Weight - Easy to handle
• Greater Safety - No Electric Hazards
• Higher Security

8. OFC Applications
• Telecommunication Network
• Junction Network & Long Distance Network
• Submarine cable
• High EMI areas
• Explosive environment
• Computer links & Local Area Network
• Cable television
• Medical Field , Automobile Field

9. Construction of Fibre
•Centre Core – Glass – More RI 8-10 micrometer
Light is transmitted through the core
•Cladding – Glass – Less RI 125 micro meter
--Outside optical layer that traps the light into the core by
Total Internal Reflection and guides the light along the core
•Primary Coating – Protection & Identification of Fibre
OFC Construction

10. TIR is achieved since
Core and Cladding
having different
Refractive Indices.
Core RI – 1.48
Cladding RI – 1.47
Principle of Working
Total Internal reflection

11. • Centre Strengthening Member – GRP, FRP
• Loose Tube Buffers – 2.4 mm Dia
• Fibres are placed inside the Buffers along with
Jelly to prevent moisture entry.
• Primary Strength Member – Aramid Yarn -Kevlar
• Inner Sheath – Black
• Outer Nylon Sheath - Orange
Construction of Cable

12. Construction of Cable
• Centre Strengthening
Member – GRP, FRP
• Loose Tube Buffers – 2.4
mm Dia, Fibres are
placed inside along with
jelly.
• Primary Strength
Member – Aramid Yarn
• Inner Sheath – Black
• Outer Nylon Sheath -
Orange

13. Loose Tube Buffers
•The Fibres are loosely drawn
inside the Buffer Tubes to take care
of Temp. Variations
•The OFC which is used outside is
known as Loose Tube Buffers
•The Correction Factor is 0.985
•985 metres of OFC will contain
1000 metres Fibre inside

14. Construction Of Cable

15. These are tight Buffered cable
•Has only one fibre per cable
•Connector ended
•Used in the indoor
applications
•Connecting equipment to
outside OFC cable
•Connecting meters to the
equipment
micro
meter
Pig Tail Cable

16. Parameters of Cabling
•Tensile Strength ( Pull)
•Crushing Resistance
•Protection from Excess Bending
•Abrasion Protection
•Anti-Twist
•Chemical protection

17. Specification Of OFC
Fibre -
Core - 8-10 Microns (Single Mode)
50 - 100Microns (Multimode)
Cladding - 125 Microns (overall Dia)
Attenuation - better than 0.5 db /KM
Primary Coating 250 Microns UV cured Acrylate
Secondary Coating –2.4 mm nylon PE Jelly filled tube
Central Strength Member – Fibre Reinforced Plastic (FRP)
Moisture Barrier- non metallic polythylene sheet free from
pinholes and other defects
Polythene sheath Polythene free from pin holes

18. Nylon Outer Sheath (0.7mm thickness)- Protective sheath against
termite & partially against rodent
Strength to withstand a load - 3X9.8 W Newtons, where W is
weight of O/F cable per KM in Kg
MAX Strain allowed in fibre - 0.25%
MAX attenuation variation - Permissible + 0.02 dB from
normal 20 degree centigrade to 60 degree centigrade
Flexibility – Maximum bending radius allowed 24d, d is the
diameter of OF cable
Cable drum lengths - 2 KM +10%
Cable ends - one end fitted with grip
Other end sealed with cap
Specification Of OFC

19. Propagation of Light inside the Fibre

20. OFC types
• Single Mode Fibre
• Multi Mode Fibre
• Plastic Optic Fibre

21. • A much smaller core Diameter
• The Core dia is 8 to 10 Micrometer
• Cladding Dia is 125 Micrometer
• Very large bandwidth
• Light can go for very long distances
Single Mode Fibre

22. Has a large Core Diameter
Core Diameter - 50, 62.5, 100 Micro meter
Cladding dia - 125 Micro meter
Light waves are dispersed into number of paths
Multiple path of light cause signal distortion
Suitable for shorter length like LAN
Multimode

23. Graded Index Fibre
Multi Mode Fibre
Step Index Fibre

24. Plastic Optic Fibre
•Large Core - 1 MM Dia
•Multimode Fibre
•Used in Automobile
Industry instead of
Copper
•MOST (Media
Orientated System of
transport )

25. OFC Sizes
•6 Fibre
•12 Fibre
•24 Fibre
•48 Fibre
•96 Fibre
Standard drum length is
2000M +10% 0r 4000 m

26. 1. Pulling Method
• HDPE pipe laying ( High density Poly ethylene )
• OFC Pulling
2. Blowing Method
• PLB – Permanently lubricated Pipe laying
• Laying the OFC through blowing method
OFC LAYING

27. •Depth – 165CM
•Top Width – 45CM
•Bottom Width –30CM
•After laying HDPE pipes, the
depth should be 150CM from the
top barrel of the pipe.
Specification of Trench

29. • Standard length of the pipe – 5 M
• Diameter of the pipe - 50mm, 75mm, 110mm
• The work is taken up in sections of 200M and
pipes are buried .
• Between two sections a gap of 2M is left
known as intermediate manhole
HDPE Pipe Laying

30. • Standard length of the pipe – 5 M
• Diameter of the pipe - 50mm, 75mm, 110mm
• The work is taken up in sections of 200M and
pipes are buried .
• Between two sections a gap of 2M is left
known as intermediate manhole
HDPE Pipe Laying

31. Stores required for 200M pipe laying
HDPE pipes 50mm - 40 Numbers
Couplers - 39 Numbers
End Caps - 2 Numbers
4mm Nylon Rope - one coil of 205 to 210M

32. •10 Sections of 200M each HDPE pipes are
buried
•Open all the 9 intermediate Manholes
•Before laying the cable, ensure no blockage
•Bring the cable drum to the center at 1000M
•Center laying method is adopted
OFC pulling method

33. At Road Crossings
•RCC pipes should be used
•The RCC pipe should extend 3M on either
side from the edge of the road.
•The HDPE Duct will be pulled inside the
RCC pipe
•The road cutting work will be done during
night times with proper warning boards.

34. At Culverts / Bridges
•Galvanised iron pipes are used on the wheel
guard / footpath
•Gradual sloping to be given on either side of
the bridge by reducing the depth of the trench to
achieve the zero depth at bridges.
•For depths less than one meter, GI pipe should
be provided and cement concreted.
•Inside GI pipes , HDPE Ducts are pulled
•The GI pipes should be cement concreted

35. At Railway Crossing
•Permission should be applied well in advance
•Cast Iron pipes are used below the tracks
•With in this CI pipe, HDPE should be drawn
•Angle of crossing should be 90 degrees
•The work is carried out by railway authorities
•Thrust boring method is used

36. Handling of Cable Drum
•Drum should never be given any shock by dropping
•Drum should not be rotated on flanges
•Cable should not be bent while uncoiling
•The radius of curvature should not be less than
60CM
•Cable should not be twisted
•Use cable grip along with anti twist device while
pulling the cable

37. OFC Pulling in the
HDPE Duct for 2KM

39. CABLE LAYING – OFC
1. Survey of Cable Route (Route PLG &
SELECTION)
2. Testing of OFC in drums before laying
3. Permission from Highways, Municipality &
Rly Authorities
4. Procurement of HDPE pipes 50mm, 75 mm,
110 mm

40. CABLE LAYING – OFC – contd.
5. Procuring RCC Pipes, GI Pipes, CI Pipes
6. Procuring Nylon rope 4mm, 12mm
7. Procuring HDPE Couplings, End Caps
8. Taking Cable trench – 1.65m depth (earth
digging)

41. Pipe Laying
HDPE pipes laid with couplings inserting 4mm Nylon
rope inside the pipe.
9.Distance between the Intermediate Man Holes –
200m
40 Nos. of HDPE Pipe – 5m each
39 number of coupling + 2 End Cap
Split RCC Pipes if required (in city limits)
10.Closing of Cable trench

42. 11.Placing Route Indicators
12.Placing Joint Indicators
13.OFC Cable Pulling or Drawing
OFC Cable is pulled in the already
buried HDPE pipe. First open all
Intermediate Man Holes. After cable is
pulled the portion of exposed OFC is
covered with Split Pipe of Higher dia at
the Intermediate Man Hole.
14.Route Index Diagram to be prepared.

43. OFC Installation into PLB Ducts

44. BLOWING METHOD
• Blowing is the process of pushing the cable
through pre – prepared, pressurized, integral
OFC ducts with the help of heavy air blowing
pressure at 10 bar plus.
• The main driving force in the technology is
blowing of air at high penetrating pressure.

45. Advantages Of PLB Ducts
•Pipes are permanently lubricated
•Lubricants are built into Polymer base
•Mechanical protection to OFC
•Empty Ducts can be placed for future
use.
•Eliminates Redigging
•Saving in Reinstatment charges

46. ADVANTAGES
• Protection to OFC cable against destructing
tensile forces.
• Work execution at a great speed with
minimum risk to OFC.
• Replacement of existing faulty cable or
Replacement within no time at a later stage.

47. PLB-HDPE Ducts
•Standard length - 200M, 1000M
•Diameter - 32/26mm, 40/33mm, 50/42mm
•Couplers will be placed for jointing two
lengths
•Nylon rope approximately 4mm dia is
placed inside the ducts.

48. Duct Laying
•Place the jack along the side of the trench
•Duct should be uncoiled from the bottom
•Drive the reel slowly to avoid over spinning
•Avoid twist and kinks
•When multiple ducts are placed in a single trench,
Duct spacer to be used so that the pipes do not cross
each other.

49. PREREQUISITE
• Duct integrity
• Duct uniformity

50. OFC Installation into Ducts
Cable Blowing
•Cable jet blowing machine with compressor is
used
•Air is blown into the Duct at high pressure &
distributed along the entire cable through Duct
•The cable should be pushed from the blowing end to
achieve more blowable length.

51. CABLE JET MACHINE
• Make: SWITZERLAND
• Cable jet machine comes with appropriate
spacers.
• These spacers range from 11 mm to 18.5
mm to suit different makes of OFC.
• The spacer suitable for sterlite 2001 make is
11 to12.5, 14-15.5 and 15-18.5.

52. PROCEDURE
• Complete duct integrity test for the entire modem
section.
• Prepare stringent drum planning for entire route
with ear marked below Points(B1, B2…..etc…,)
• Transport the ear marked drums to the specified
below points and uncoil the drums into figure “8”
formation.
•

53. • Prepare the cable end suitable for
blowing by adding a spacer heading
bullet.
• Place cable jet machine inside the
blow pit and fix the top cover of the
jet machine.

54. PROCEDURE CONTD…
• Insert sponge into the duct and fix the top cover
of the jet machine.
• Fix the air – blowing hose pipe to the cable jet
machine.
• Start the compressor and blow air at 10 – bar
pressure.

55. • Confirm the receipt of sponge at the
other end of the duct.
• Remove the top cover of the cable jet
machine, insert the spear headed
Cable end into the duct and restore the
top cover

56. PROCEDURE CONTD…
• Remove the jet machine and carefully normal
the loop by lowering the duct.
• Tighten the coupler
• Continue the same for other modem section.

57. PRECAUTIONS
• Provisioning for extra cable length for bends
and shrinkage of duct during drum planning.
• Care to be taken while lowering the duct at the
end of blowing operation.
• Personnel must be beware of high operating
air pressures

59. Factors Influencing
Blowable length
•Inside diameter of the duct
•Outside Diameter of the cable
•Weight of the cable
•Number of slopes
•cable stiffness
•Straightness of the route
•Ambient temperature

60. Blowing Chamber
Chambers are placed at a distance of one KM
Size of the blowing chamber is 3M X 1MX
1.5M(LXWXD )
These are temporary chambers and refilled
after accomplishing blowing operation
Average blowable length is 700M to 2000M
depending upon the factors

61. Submarine Cable Laying
Cable Laying

62. Submarine Cable Repairing
Cable Repairing

64. Fibre In The Loop/
Fibre in Access Network

65. •Fibre to the curb
(FTTC)
•Fibre to the
building(FTTB)
•Fibre to the
home(FTTH)

67. Submarine OF
cable

68. Submarine OF Cables
•High B/W, long repeater spans
make the OF Cable Suitable for
undersea operations.
•Several countries are
interconnected.
•They replace the conventional
analog Coaxial.

69. Submarine Cable
Construction
•Central fibre
stranding
member(copper
rod)
•Inner line Fibres.
•Insulation and
copper sheath
line.
•Outer armoring
line(steel rods)

70. Submarine OF
Cables

71. Glass Necklaces
•Fibre Link Around
the Globe(FLAG).
•SEA-ME-WE.
•Trans Atlantic
Cables (TAT)
•Trans Pacific
Cables (TPC)

72. Fibre Optic Lighting

73. Fibre Optic
Lighting
•Large core fibres used for
transmitting visible light.
•Remote light source and
flexible cable that can be bent.
•No electric current passes
from the source.
•Safe for swimming pool,
landscape lighting.

74. Fibre Optic Lighting
•Two types available.
1.Side Light.
Light available
along the entire length
like neon.
2.End Light.
Light is visible at
the end of the cable.

75. Free Space
Optics

76. Optical Wireless
•Light as an
electromagnetic
wave can travel
thro free space
also.
•Instead of fibre it
can be FREE
SPACE OPTICS

77. ‘Wireless’
Optics?
Fiber replaced by free space
oChannel characteristics
not in control
oTransmitter and Receiver
essentially the same.

78. Plastic Fibre
Solution for industrial
automation

79. Plastic Fibre
Industrial control automation
depends on copper cable
Electromagnetic Interference in
Copper
Narrowing of difference in cost
between copper and fibre has
driven the need for a changing
into POF.

80. Fibre connectors in
Vehicle
MOST- Media
Orientated System of
transport by car
makers
Facilitate
standarised
connectors

81. •Large scale use of POF in
factory networking for
sending high speed data
•Car connectors
• A total Solution for
industrial control
applications
PLASTIC OPTIC FIBRE

82. Microfluidic fibres
Transmit as well as process
light

83. Construction
These fibres are hollow
perforated with channels
Each fibre looks like a bundle
of drinking straws
Fluid with in the fibre is
responsible for transmitting
light of different colours

84. Advantages
•Cheaper and strong like conventional fibre
•The Microfluidic Fibres can be used for
transmitting light of different colours
•Switches or transistors can be installed in
the midway
•Can act as both transmission channel and
filter
•Can be switched to relay one signal and
then the another

85. Telecommunications
•Today’s Telecom is
growing
“Faster- Higher-
Stronger”.
•The contribution of
fibre towards this
trend is a major one.
•All optical network
will emerge.

87. 1844 Telegraph 5 bits /sec
1876 Telephone 2 kb/sec
1956 Trans Atlantic 1152 kb/sec
1983 OFC 45000 kb/sec
Today 2-3 Terra bit/sec
• The Transport Capacity of
OFC advances by 100 times
every 10 years
Improvements in Fibre

88. For the years to come,
the primary carrier for
broadband will be
fibre-optic cable to
businesses, institutions,
and homes, combined
with copper and with
satellite as back-up
option for remote areas
FUTURE

89. Fit
Fibre
and
Forget

90. THANK
YOU