A Presentation on

OPTIC FIBRE CABLE

BY Dhruv Infratel PVT LTD

Telecom Training Centre

(ISO 9001:2000 Certified)

Delhi-100075 Email – Info@dhruvinfratel.com

OPTIC FIBRE CABLE

Objectives• What is OFC?

• OFC Advantages

• OFC Types & Applications

• Specifications

• Future Trends

•OFC Installation

• Pulling Method with Nylon rope

• Blowing Method

Limitations of copper network

•Copper is costlier and scarce material.

•Fault prone.

•Maintenance difficult

•Vulnerable for EMI.

•Installation time consuming.

Limitations of copper based network

•Expansions make congestions in MDF •B/W LIMITED.•Loop Resistance restricts the length of operation.

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.

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

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

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

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

•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

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

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

Construction Of Cable

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

micrometer

Pig Tail Cable

Parameters of Cabling•Tensile Strength ( Pull)

•Crushing Resistance

•Protection from Excess Bending

•Abrasion Protection

•Anti-Twist

•Chemical protection

Specification Of OFCFibre - 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

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

Propagation of Light inside the Fibre

OFC types•Single Mode Fibre

•Multi Mode Fibre

•Plastic Optic Fibre

•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

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

Graded Index Fibre

Multi Mode Fibre

Step Index Fibre

Plastic Optic Fibre•Large Core - 1 MM Dia

•Multimode Fibre

•Used in Automobile Industry instead of Copper

•MOST (Media Orientated System of transport )

OFC Sizes

•6 Fibre

•12 Fibre

•24 Fibre

•48 Fibre

•96 Fibre

Standard drum length is 2000M +10% 0r 4000 m

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

•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

•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

•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

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

•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

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.

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

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

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

OFC Pulling in the

HDPE Duct for 2KM

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

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)

Pipe LayingHDPE 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

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.

OFC Installation into PLB Ducts

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.

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

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.

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.

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.

PREREQUISITE

• Duct integrity

• Duct uniformity

OFC Installation into DuctsCable 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.

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.

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.

•

• 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.

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.

• 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

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.

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

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

Blowing ChamberChambers 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

Submarine Cable Laying

Cable Laying

Submarine Cable Repairing

Cable Repairing

Fibre In The Loop/Fibre in Access Network

•Fibre to the curb (FTTC)

•Fibre to the building(FTTB)

•Fibre to the home(FTTH)

Submarine OF cable

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.

Submarine Cable Construction

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

Submarine OF Cables

Glass Necklaces

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

Fibre Optic Lighting

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.

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.

Free Space Optics

Optical Wireless

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

‘Wireless’ Optics?

Fiber replaced by free spaceoChannel characteristics not in controloTransmitter and Receiver essentially the same.

Plastic Fibre

Solution for industrial automation

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.

Fibre connectors in Vehicle

MOST- Media Orientated System of transport by car makers

Facilitate standarised connectors

•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

Microfluidic fibres

Transmit as well as process light

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

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

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.

1844 Telegraph 5 bits /sec

1876 Telephone2 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

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

Fit Fibre

and

Forget

THANK YOU