3 ways to construct fibre-to-the-home

8/2/2019 3 Ways to Construct Fibre-To-The-Home

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NETWORK CONSTRUCTIONDESCRIPTION

3 ways to construct

Fibre-To-The-HomeComplete, high-quality networks at low cost

issued 2005-11-17


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Contents

Contents............................................................................................................................. 2Our experience offers you high quality at low cost .................................................................. 1Definitions, network structure................................................................................................ 2

Controlling factors for network construction............................................................................ 3Material and technology ...................................................................................................... 4Documentation ................................................................................................................... 7General construction methods .............................................................................................. 7Construction method I - Robust cable and micro cable ............................................................ 8Construction method II - Micro cable................................................................................... 10Construction method III Aerial cable ................................................................................. 13Tips and advice................................................................................................................. 15Dictionary......................................................................................................................... 15Dictionary......................................................................................................................... 16

Appendix 1 - Table for duct estimation ................................................................................ 17Appendix 2 - Traditional fibre optical cable.......................................................................... 18Appendix 3 Fibre optical micro cable ................................................................................ 21Appendix 4 - Fibre optical cable for aerial installation ........................................................... 23Appendix 5 - Stations......................................................................................................... 24Appendix 6 Fibre optical junction boxes ............................................................................ 26Appendix 7 Fibre optical joint and termination cabinet for wall installation ........................... 29Appendix 8 Fibre optical customer terminal for wall installation ........................................... 31Appendix 9 Accessories for aerial cables ........................................................................... 32Appendix 10 - Other material............................................................................................. 33


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Our experience offers you high quality at low cost

Nexans has supplied optical cable systems forunderground and aerial installation for nearly20 years. Our experience has allowed us to

create the Nexans Citynet Solution, a completesystem of tried and tested components andsolutions. In this booklet, we will examine thealternatives available for constructing the lastmile, or the fibre-to-the-home network(FTTH), with high quality at low cost.

We will describe below how the networkstructure can be constructed, the necessaryconsiderations, construction methods andsuitable products for building FTTH networks.

The challenge is to construct a network from

an urban junction or area junction all the wayto a site or individual customer. This must bedone at reasonable cost, with the right qualityas well as considering future upgrading.

Network structure7A typical example is shown below, of what thenetwork structure could look like in an area

node. The illustration shows a section of theurban network (yellow) that contains an areajunction (3).

From the area junction (3), the network branchesout into the area network (purple) to varioustypes of building. In each area, the networkbranches further into a property area node (4) toeach property.

The property node (5) marks the end of thenetwork. From this point, each property owner isresponsible for further branching to each

customer like companies in commercialproperties, customers in an apartment block orin their own private house.

Example of network structure


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Definitions, network structure

National backbone networkThe national backbone network links eachregion in the country. The backbone network is

linked to other national backbone networks bythe international network.

Regional nodes (1)regional network (orange __________________ )Traffic is interchanged in inter-city nodesbetween the national backbone network andthe city network. Inter-city nodes are located inthe centre of the inter-city network. Thisnetwork links all the towns in a municipalitywith each other

Urban junctions (2)

Urban network (yellow ___ _______________ )Each town in a municipality has a urbanjunction. The network branches out from theurban junction to the urban network.The function of the urban network is to linkeach area in a town to each other.

Area junction (3)Areanetwork (purple __________________ )Each area has it own area junction. The network

branches from here into an area network.

Property area node (4)Property area network (green ___ ___ ___ _________ )In urban areas (like town centres, residentialareas or industrial areas) the area network isfurther branched into a property area networkwhich reaches individual buildings. Distributionis done by property area nodes. Individualcables are then run directly to single, remotebuildings in rural areas.

Property nodes (5)

These nodes form the final destination of theurban network, and are where traffic isinterchanged between the urban network andeach property owners network.

Principle illustration of network structure


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Controlling factors for network construction

The size and character of a town influencethe way that the network is set up.

In towns and in larger conurbations, thenetwork branches from node 2 to each areavia node 3. Nodes 2 and 3 in the networkstructure correspond in reality to some type ofarea with indoor climate. They contain activecomponents such as switches (routers).

Other equipment consists of passivecomponents such as distribution frames andcables.

As for smaller towns and villages, a node 3 isnot needed. Cables are then run direct from

node 2 to node 4, which forms a physicaljunction in the network to the buildings. As arule, not more than 24 households orsubscribers are connected to the samejunction in node 4.

Ring network or star network?The network is designed as a ring or a star,depending on the quality criteria chosen. A star

network branches in a hierarchical structure,whereas a ring network is shaped like a ring.

The advantage of a ring network is thatredundancy is built into the network, i.e. if acable in a ring network is cut by an excavator,the signals have an alternative pathway andcustomers still have contact with the network.If a ring network is constructed, the number offibres in the cable should be chosen to suit thenumber of residents along the entire ring. If astar network is built, the number of fibres shouldbe enough for the number of subscribers in the

specific area.

Future requirementsWhen a project is planned, it is always importantto consider future requirements. It can beregarded as being reasonable to allocate 4fibres per customer to cover that requirement. Inaddition, you also have to consider mid- andlongterm upgrading.

Ring network

Ring topology

Star topology


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Material and technology

If you are going to build an FTTH network at thelowest possible cost, while maintaining quality,you have to realise that quality is judged by

criteria such as reliability, simple maintenance,level of upgradeability and aesthetic design.

The choice of cables and ducts is very importantfor the quality of a network solution, but it alsohas a strong influence on the cost (CAPEX) of thepassive network. It is important to choose theright material for each situation.

Our general recommendation is to use robustunderground and aerial cables in combinationwith micro-cables to give good quality and goodeconomy (CAPEX/OPEX).

CablesDifferent cables have different designs, functionand quality. Let us take a closer look at: robust underground cable

micro cable aerial cable

Robust underground cable is a traditional cablesince it was the first type marketed when opticalfibre technology was introduced. These cablescan contain several hundreds of fibres and have

been designed with mechanical protection towithstand the forces involved in pulling the cablein ducts or burying it directly.

Robust underground cables are tried and testedin many installations and have proven long life.Installation methods have been improved overthe years, resulting in the development ofslimmer and lighter cables.

The next stage in developments was small-sizeducts, to use existing duct paths that were

already full of cables. This led to development ofthe micro cables in its turn.

Micro cables have been designed and adaptedfor installation in small ducts, called microducts. Their small dimensions mean that

mechanical strength has been sacrificed forsize. Micro cables can contain up to 96 fibresper cable, depending on outer diameter.

Aerial cables, which are robust cables, are aswell tested as underground cables. Aerialcables are suitable for use in small towns withexisting aerial cable installations for electricityor telephone distribution, where the existingpoles can be used. In areas where groundconditions are such that an undergroundnetwork can not be installed, aerial cables areused instead.

DuctingUsing ducting instead of direct buried cableinstallation has several advantages:

improved protection against mechanicaldamage to the cable

possible to extend the fibre network at areasonable cost

possible to change a cable with a minimalamount of labour

Ducting can consist of optical cable protectionpipes, micro ducts or multi-ducts.

Optical cable protection pipes and most multi-ducts are designed to be installed directly intoground. Micro ducts are either installed in amulti-duct or are blown into an optical cableprotection pipe later on.

Ducting should be installed together, whereverpossible, to reduce installation costs.

Please refer to industry standards for moreinformation about duct installation.


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Examples of combinations of ducting and cables are shown below.

Optical cable protection pipes are available

in several different dimensions, e.g. 50/40,40/32 or 16/12.Dimensions are chosen to suit thedimension(s) of the cable(s) or micro ducts.

Optical cable protection pipes 40/32 and16/12

Optical cable protection pipe with robustunderground cable

Optical cable protection pipe with micro ducts and amicro cable in one of the micro ducts

Micro ducts are relatively small, flexible and light

tubes with external diameter less than 16 mm.

Micro duct dimensions are chosen to suit themicro cable dimension.

Micro ducts of different colours and dimensions

Multi ducts consist of a number of micro ductsheld together by a plastic sheath.

Multi duct (several micro ducts with common sheath)


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Splicing techniques

The node that we will refer to in thedocumentation as the station is the lastnode before the building, containing active

equipment, where cross connection (patching)is also done. The splices made at the stationare made with pigtails or fan-outs in thedistribution boxes.

If pre-connectorised distribution boxes areused, joints are either made indoors injunction modules or outdoors in junctionboxes. The joints made at the station formpart of the station and are not mentioned asa separate item.

In theproperty area node (node 4), cables

can be joined in different ways. Joints can beinstalled in manholes, cabinets at theroadside, indoors or on poles. Material, suchas junction boxes, is selected to suit theenvironment where the joint will be located. Apure butt joint can be made at this point, i.e.all fibres which come into the junction pointare butt jointed to another fibre, or you cando a so-called mid span joint.

A mid-span joint is when the entire length ofan optical cable is laid, irrespective of

whether it is a ring or star network. Sufficientcable is installed at each joint (about 20 m),so that a mid-span joint can be made lateron.

When a joint is to be made, the cable is openedand only some of the fibres in the cable are cutand branched out to the fibres in another cable.

The remaining fibres remain uncut and pass bythe junction point on their way to the next pointon the cable route.

The advantage of building networks in thismanner is that it saves time and money duringinstallation. It reduces the number of welds andthus reduces the total attenuation in the fibre.

If a mid-span joint is to be made on a micro-cable in a micro duct, it is a good idea to installthe micro duct in the junction manhole with thesame length that the cable will have later on.

The micro duct can subsequently be cut when thecable is to be joined.

The illustration below shows two manholes withloops of micro cable in micro duct prepared forlater joining.

Installation of micro duct and cable for subsequentjointing.


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Documentation

Cables and ducts must be documented bynormal cartography and by optical

measurements. Tubes and fibre ribbons injunction boxes and distribution boxes must benumbered. All optical cables must be markedwith their cable number.

Distribution frames, cabinets and distributionboxes should be marked with the ownersname and any map coordinates. In addition,an assembly drawing must be made showingthe distribution boxes or the positions of thecomponents in cabinets or frames.

There will be a large amount of ducting at

each junction point. For this reason, becareful to mark all ducting correctly with theaddress of each building.

A line schedule is needed to give a goodperspective of the network.

General construction methods

The advantages and disadvantages of each typeof network construction mean that must be

considered when choosing type of cable. Thechapters below describe the installation practicethat we regard as most common:

I. Robust underground cable and microcable

II. Micro cableIII.Aerial cable

The solutions that we describe contain all theessential passive components needed:

ducting fibre-optical underground cables, micro

cables and aerial cables

distribution frames and distribution boxes

junction boxes and termination cabinets accessories for each product

Our product range, which part of the NexansCitynet Solution, includes all the above productsexcept for the ducts. Appendices 1-8 show ourproducts, everything from cables to accessories.Please contact Nexans for full orderinginformation.


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Construction method I - Robust cable and micro cable

This construction method uses robust cablebetween the station and the junction point,whereas micro cable is used from the junction

point to the building.

Cable and ductsFrom the station (node 2 or 3,) an opticalcable protection pipe is installed, throughwhich a robust cable is later blown along aspecific distance, where all the junction pointsare positioned (node 4), depending on howthe residential area is laid out.

If a star network has been chosen, the opticalcable protection pipe is terminated at the lastjunction point. On the other hand, if a ring

network has been chosen, the optical cableprotection pipe passes through all thejunction points until it arrives at the station.

The choice of optical cable protection pipe isdetermined by the cable you want to installand by future needs. Appendix 1 shows thesize of pipe that suits each cable. Our robustcables are found in appendix 2.

From the junction point (node 4) to eachbuilding (node 5), an optical cable protection

pipe of dimension 16/12 is installed to offerthe most economical solution. Ducting isdrawn all the way to the building.

If a customer does not initially want to beconnected, a loop is installed at the propertyboundary. If you do not want to have a looplying outside the boundary, the duct isterminated and plugged. When the customersubsequently wants to be connected, the ductis extended.

In new construction (green field), you mightdecide to use a electrical utility distribution cablewith an integrated low-friction pipe, where the

optical cable can be installed later on (NexansDuolink).

From the junction point (node 4), it may besuitable to install multi-ducts for practicalreasons in some cases, since a concentration ofmany ducts could occur at that point.

Ducts should be installed together wheneverpossible, to reduce installation costs.

Micro cable is used for the last link between thejunction point and the building, please refer to

appendix 3.

StationYou can choose to install stations in differentways, depending on the town or the size of thearea. If the station has 1000 terminations, it isa good idea to use a multi-fibre system, pleaserefer to appendix 5.

In a smaller station, it is a good idea to usetraditional pre-terminated distribution boxes andcabinets. You could also choose accessories

intended for termination on site, please refer toappendix 5.

If a multi-fibre system (high fibre count) ischosen, the junction between the indoor cableand the incoming cable is made in a junctioncabinet indoors.

If traditional distribution boxes are used, jointscan be made in a junction cabinet, but it is morecommon practice to use a manhole outdoors,which contains junction boxes.


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Junction pointJunction points are most commonly made ina junction manhole or cabinet. The bendingradius of the able and the size of the junction

box must be considered when the manhole orcabinet is chosen. The junction boxes inappendix 6 allow a mid-span joint to bemade. The box is also prepared forconnection to the many micro-cables thatenter buildings. In multi-dwelling properties,the junction points can be located indoors.

The cable which joins all junction points mustbe prepared in accordance with theinstructions for the cable and the junction boxselected. The fibres required for each junctionpoint are cut and looped into the box. The

remaining fibres continue onwards to the nextjunction point. When a customer is to beconnected, the micro cable is then joined toselected fibres from the previously preparedcable. If redundancy is required, fibres canalso be jointed in the opposite direction.

BuildingThe cable is terminated in a patching field orwall cabinet (depending on the number of fibres)in the basement or other suitable location.

Please refer to appendix 8.Pre-terminated patching fields and wall cabinetsare available. If one of these is used, the cablemust be installed in the direction from thebuilding towards the junction point.


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Construction method II - Micro cable

This construction method uses micro cableall the way between the station via thejunction point to the building.

Cable and ductsThe best way to install micro cables is inmicro ducts. The choice of micro cable(please refer to appendix 3) governs thechoice of micro duct. There is a table inappendix 1 showing the size of micro ductwhich suits the chosen cable diameter.

So-called multi-ducts are prepared formicro-ducting. Our recommendation is thattraditional optical cable protection pipesshould be used, and micro-ducts should be

blown in afterwards. This does not restrictyour choice of cables or micro-ducts lateron.

From station (node 2 or 3) an optical cableprotection pipe is installed, through whichmicro ducts and micro cables are laterblown along a specific distance, where allthe junction points are positioned (node 4),depending on how the residential area islaid out.If a star network has been chosen, the

optical cable protection pipe is terminated atthe last junction point. On the other hand, ifa ring network has been chosen, the opticalcable protection pipe passes through all thejunction points until it arrives at the station.

When you install micro cable in a starnetwork, you should install the amount offibre that meets requirements for the initialinstallation. Then add an empty micro ductwhich can be used for subsequent expansion.

If a ring network is constructed, micro ducts areblown from one station along the entire extent ofthe protective pipe. Branching into micro ducts is

done later on. The number of micro ducts neededdepends on the area in question. If the area issmall, only one optical cable protection pipe isneeded, of dimension 16/12 mm, through whichone micro cable is blown.

There are several methods of installing micro-cables in a ring network. Three different methodsare shown below.

Alt 1. New branchOne or more micro-ducts are extended andcontinue along a new branch. The micro cable is

installed uncut along the entire distance to thelast junction point at the end of the new branch.Mid-span jointing is then done at all junctionpoints on the cable, up to the end point.

Alt 2. The cable is terminatedA micro cable is installed in a micro duct from thestation to the junction point where it is terminated.

Alt 3. Redundant installationA micro cable is blown through a micro ductalong the entire length of the protective pipe, to

achieve redundancy. Later on, the cable is cut atthe junction point, or a mid-span joint is made. Ifbuildings are erected along the cable route lateron, and if the number of fibres has beengenerously chosen, it will be possible to supplyfurther nodes from the same cable.


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Three ways to install cable in a star network

In alternatives 1 and 2, the section of themicro duct which continues after the branch

or junction is not used. Cables can be blownfrom the opposite direction in most cases, foruse by other site areas or to retrofitredundancy into an existing site area.

When a cable is going to be installed, theoptical cable protection pipe is opened ateach junction point and the selected microducting is branched (there are various typesof branch pipes and quick-connectionterminations that can be used).

From each junction point (node 4) up to each

building (node 5, an optical cable protectionpipe is installed. The most economicalinstallation is made with dimension 16/12.The ducts are installed right up to eachbuilding.

If a customer does not initially want to beconnected, a loop is installed at the property

boundary. If you do not want to have a looplying outside the boundary, the duct isterminated and plugged. When the customersubsequently wants to be connected, the ductis extended.

In new construction (green field), you mightdecide to use a electrical utility distribution cablewith an integrated low-friction pipe, where theoptical cable can be installed later on (NexansDuolink).

From the junction point (node 4), it may be

suitable to install multi-ducts for practicalreasons in some cases, since a concentration ofmany ducts could occur at that point

Ducts should be installed together wheneverpossible, to reduce installation costs.Recommended cables are described in appendix3.


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StationYou can choose to install stations in differentways, depending on the town or the size of thearea. If the station has 1000 terminations, itis a good idea to use a multi-fibre system,

please refer to appendix 5.

In a smaller station, it is a good idea to usetraditional pre-terminated distribution boxesand cabinets. You could also chooseaccessories intended for termination on site,please refer to appendix 5.

If a multi-fibre system (high fibre count) ischosen, the junction between the indoor cableand the incoming cable is made in a junctioncabinet indoors. If traditional distribution boxesare used, joints can be made in a junction

cabinet, but it is more common practice to usea junction manhole outdoors, which containsjunction boxes.

Junction pointJunction points are most commonly madein a junction manhole or cabinet. Thebending radius of the able and the size ofthe junction box must be considered whenthe manhole or cabinet is chosen. Inapartment blocks, the junction point can belocated indoors.

A junction box is used at each junctionpoint, using a suitable cable gland formicro cable. If a mid-span joint is to bemade, a cable gland is needed for this aswell.

The cable which joins all junction points must beprepared in accordance with the instructions forthe cable and the junction box selected. The fibresrequired for each junction point are cut andlooped into the box. The remaining fibres continue

on uncut to the next junction point. When acustomer is to be connected, the micro cable isthen joined to selected fibres from the previouslyprepared cable. If redundancy is wanted, fibrescan also be jointed in the opposite direction.

The service cable (a micro cable in this case) isprepared in accordance with the instructions forthe cable and the junction box selected. If a mid-span joint is made, the fibres required are cut andlooped into the box. The remaining fibres continueon uncut to the next junction point. The fibres to beconnected are joined to micro cable which runs to

each building in the normal way.

BuildingThe cable is terminated in a patching field or wallcabinet (depending on the number of fibres) in thebasement or other suitable location. Please refer toappendix 8.Pre-terminated patching field and wall cabinetsare available. If one of these is used, the cablemust be installed in the direction from the buildingtowards the junction point.


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Construction method III Aerial cable

In this construction method, aerial cables areused between the station and the junctionpoint, whereas micro cables are used from

the junction point to the building.

Cables and ductsFrom the station (node 2 or 3), the aerialcable is run to a junction point located on orclose to a pole. When aerial cables are used,no ducts are needed.

If the installation is for a single property in arural area, no junction point is made. Theaerial cable is run directly down the pole toan underground duct that reaches theproperty. It is, of course, possible to have an

aerial cable that stretches from the last poleto the building. The cable dimension andnumber of fibres is determined by the area(s)in question and the span between each pole.Our aerial cables are shown in appendix 4.

Please refer to appendix 9 for accessoriessuch as tension sets, suspension sets, down-lead clamps etc. For further information,please refer to the installation guide Opticalcable system for aerial cables, Max 55 kV.

From each junction point (node 4), located onor beside a pole, an optical cable protectionpipe of dimension 16/12 mm is installed upto each property. If possible, a loop shouldbe installed at the property boundary or theduct should be terminated with an end plug.

When a property is to be connected later on,the duct is extended. We recommend thatmicro cable should be used for the stretchbetween the junction point and the building.

StationAerial cables are frequently used in smallertowns and areas where it is advantageous to use

aerial cable. For this reason, it is probable thatthe station will serve a smaller number ofcustomers which in turn involves a smallernumber of fibres. In this case, it is a good ideato use pre-terminated junction boxes which arelocated in cabinets or frames at the station.

Alternatively, you can choose to use accessoriesdesigned for termination on site, please refer toappendix 5.If it is a large station, where there is only a smallpercentage of aerial cable, it is of coursepossible to use the multi-fibre system (high fibre

count), please refer to appendix 5.

If pre-terminated distribution boxes are used, thecable between the box and the aerial cableshould be joined in a junction box located in amanhole or junction cabinet outside the station.


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Junction pointWhen joints are made in aerial cables, thereare various ways to protect cables and boxes,either in a cable reel on the pole, junctioncabinet on or beside the pole, junction

manhole beside or adjacent to the pole. Thechoice is governed by ground conditions,land owners, costs, height above ground andaccessibility. The choice should also considerthe cable bending radius and the size of thejunction box.

If the installation contains a joint between amulti-fibre aerial optical cable and severalmicro cables, a junction box with cableglands for micro cable is used, please refer toappendix 6.

In this case, it can be suitable to use acabinet, since this makes it easer to managemany cables. Aerial cables are also suitablefor mid-span jointing if there are manybranching points along a line.

The fibres to be used are joined to the microcables which go to each building in ducts inaccordance with the previously mentionedprinciples. If redundancy is required, cablescan also be jointed in the opposite direction.

BuildingThe cable is terminated in a patching field orwall cabinet (depending on the number of fibres)in the basement or other suitable location.Please refer to appendix 8.

Pre-terminated patching field and wall cabinetsare available. If one of these is used, the cablemust be installed in the direction from thebuilding towards the junction point.


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Tips and advice

Installation with compressed air (blowing) All ducts should be the low-friction type with smooth or ribbed silicone coated inside. It is a general rule, for best results, that the inner diameter of the pipe should be 1.5 2 x

cable outer diameter. Another dimension commonly used is that the cable should achieve60% filling.

If the air streams are to function satisfactorily, the pipe must not be squeezed. With as littleas 15% of squeezing, the air streams are negatively affected.

A gauge plug should be sent through the pipe before it is used, to ensure acceptable pipeperformance. The gauge should have slightly smaller diameter than the inner diameter ofthe pipe.

If a slim cable is used in a large pipe, you can compensate the problem by using a pullshuttle or you can blow a narrow pipe through the existing pipe.

You can blow a cable or pipe into an existing pipe provided that the pipe diameter is largeenough.

You can blow micro ducts into a pipe with existing cables provided that the pipe diameter islarge enough.

The distance that a cable can be blown depends to a large extent on how the ducting hasbeen arranged (no squeezing, sharp angles etc).

Blow the pipe clean with sponge rubber etc. Check that it comes out clean.

Use lubricant carefully. Too much can affect the result negatively.

Fibre optical cable If long lengths are installed outdoors, PE sheathed cable with a slotted core are

recommended. No more than 5 m length of PE sheathed cable should be installed indoors unless it has

been fire/flame protected (refer to national regulations).

Cables with a slotted core should be selected for best mechanical protection. Bending radius during installation is 20 times outer diameter. Bending radius for installed cable is 15 times outer diameter.

Never exceed the tension strength values specified in the data sheet.

Fibre optical components Use the same type and manufacturer of the fibres, or make sure that the fibres are

compatible in all cables, irrespective of whether they are intended for outdoor installation inducts or are in a pre-terminated distribution box, fan-out, fibre tail or distribution cable.

Use SC connectors and adapters in your network if possible. This is because of their low costand wide commercial availability.

Always specify the following parameters for your fibre-optical terminations: attenuation,back reflection attenuation and dimension such as radius, offset and fibreprotrution/insertion. These are the parameters that determine the quality of the product andprovide secure, reliable function in future.

Junction boxes for outdoor installation in manholes or direct in the ground must comply withIP68 classification.

Pre-terminated distribution boxes should preferably be used when cables are to beterminated in a cross-connection point. This is due to quality, cost and future reliability.


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Dictionary

Fibre type Fibres standardised according to ITU-T. For single mode G.652 and formultimode G.651.

Pre-terminated Factory assembled ready-made passive fibre-optical termination

equipment located in some kind of box with the desired length of cable.Distribution box Box for installing fibre-optical terminations.Mid-span joint An uncut cable is stripped in the middle of a length, where only selected

fibres are cut and joined.Micro cable Cables intended to be blown through micro ducts.Micro duct Small, light, flexible tube with outer diameter less than16 mm.Multi duct Several micro ducts with a common sheath.ODF Optical distribution fieldOptical cableprotection pipe Duct for installation of cables or micro ducts.Redundancy Several alternative communication paths.Slotted core A GRP (glass fibre reinforced plastics) core is coated with polyethylene

which is formed into a slotted profile.Station A node 2 or 3 in a network is a physical station.Junction point A node 4 in a network is a physical junction point in a junction box etc.

Wall box Fibre optical termination in a building (node 5), max 4 fibres.Wall cabinet Fibre optical termination in a large building, up to 72 fibres.


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Appendix 1 - Table for duct estimation

This table is intended to show the pipes which suit various cable dimensions, by rule of thumb. Thisis intended to create the best conditions when you blow cables through ducts. No blowing lengthsare included in this table, since this is largely governed by how the ducts are installed.

Cable pipe dim 50/40 40/32 32/28 25/21 20/16 16/12 12/9 10/812/8

7/5,5 5/3,5 Mid

sp

Blue

seg.

Tens.

(kN)

Comp

(kN)

Robust duct cableNo. of

fibres

Cable

dim

GASLDV 384 19,8 1,5 3

192 16,4 1,5 3

96 13,2 1,5 3

48 10 1 1

4-24 7,9 0,7 1

GRSLDV 96 15,4 2 3

72 13 2 3

12-48 10,8 2 3

GRHLDV 192 18,5 2 2

96 11,1 1,5 2

12-72 10 1 2

Robust combi-cable

Indoors/outdoors

GASQBDUV 384 21 1,5 3

192 18,2 1,5 3

96 12 1,5 3

48 10,7 1 3

4-24 9,2 0,7 3

GRSQBDV 96 16,4 2 3

72 12,9 2 3

4-48 10,4 1 3

GRHQBDV 144 15,2 1 2

96 11,8 1 2

72 10,8 1 2

GAGQBDUV 8-12 7 0,4 1

4 5,5 0,4 1

Micro cable

MB-0814 B-Lite 96 7,2 0,7 1

MB-0613 B-Lite 48-72 5,4 0,7 1

UB32 B-Lite 24 4 0,15 2

UT30 B-Lite 8-12 3,9 0,15 2

UT21 B-Lite 2-6 3,3 0,15 2

UT16 B-Lite 2-4 2,5 0,15 2

Cable data

Best ducting type, according to rule of thumb

Good ducting type, according to rule of thumb

Possible ducting type

Legend


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Appendix 2 - Traditional robust fibre optical cable

Fibre-optical cables with slotted core and fibre ribbons

GASLDV 4-384 fibres

Outdoor installation in ducts Slotted core for extra mechanical

protection Fibre Ribbon

Optical filling compound

Halogen-free polyethylene sheath

Fibre-optical cable, very suitable for blowinginto opto-ducts. The cable is available with alarge number of fibres, as many as 384 fibres.The fibres are joined together in 4 or 8 fibreribbons (8 fibre ribbons for 96,192 and 384fibres).

GASQBDUV 4-384

Indoor and outdoor installation in ducts Slotted core for extra mechanical protection Fibre Ribbon

Water-swelling material

Halogen-free flame-proofed sheath Fire spread class F4C

Dry fibre-optical combined cable for indoorinstallation and outdoor installation in ducts. Thefibres are joined together in 4 or 8 fibre ribbons(8 fibre ribbons for 96,192 and 384 fibres). Thecable complies with fire requirements under IEC60332-3, cat C which corresponds with firepropagation class F4C under SS 424 14 75.


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Fibre-optical cables with slotted core and loose tubes

GRSLDV 4-96 fibres

Outdoor installation in ducts Slotted core for extra mechanical

protection Polyester tubes with optical filling

compound

Optical filling compound for lengthwayswater-tightness


Fibre-optical cable, very suitable for blowinginto opto-ducts. The tubes are well-protectedinside the slotted core.

GRSQBDV 4-96 fibres

Indoor and outdoor installation Slotted core for extra mechanical protection Polyester tubes with optical filling

compound

Water-swelling tape Halogen-free flame-proofed sheath Fire spread class F2

Dry fibre-optical combined cable for indoorinstallation and outdoor installation in ducts.The cable complies with fire requirements underIEC 60332-3, cat C which corresponds with firepropagation class F2 according to SS 424 1475.


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Fibre-optical cables with Loose Tube around a central strength member

GRHLDV 12-192 fibres Outdoor installation in ducts Centred glass fibre strain relief

Polyester tubes with optical fillingcompound

Optical filling compound

Halogen-free polyethylene sheath Single centre span

Fibre-optical cable, very suitable for blowinginto opto-ducts. Does not contain a slottedcore.

GRHQBDV 12-144 fibres Indoor and outdoor installation Centred glass fibre strain relief

Polyester tubes with optical filling compound Water-swelling tape

Halogen-free flame-proofed sheath Fire spread class F2

Single centre span

Dry fibre-optical combined cable for indoorinstallation and outdoor installation in ducts. Thecable complies with fire requirements under IEC60332-1 which corresponds with firepropagation class F2 according toSS 424 14 75.


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Appendix 3 Fibre optical micro cable

Fibre-optical micro cables with micro tubes Fibre-optical micro cables with microtubes in a Central tube

MB-0814 B-Lite 96 fibresMB-0613 B-Lite 48-72 fibres Outdoor installation in ducts Centred glass fibre strain relief

Up to 8 micro tubes

Aramid yarn with swelling powder forincreased strain relief and lengthways watertightness


Single centre span

Cable designed for blowing into micro ducts.

UB32 B-Lite 24 fibres Outdoor installation in ducts Central tube with optical filling compound

3 micro tubes in a Central tube

Aramid yarn for strain relief Halogen-free polyethylene sheath



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Fibre optical micro cables Cables with fibre ribbons in central tubewith loose fibres in central tube

UT16 B-Lite 2-4 fibresUT21 B-Lite 2-6 fibresUT30 B-Lite 8-12 fibres Outdoor installation in ducts Central tube with optical filling compound

Loose fibres in Central tube

Aramid yarn for strain relief Halogen-free polyethylene sheath


GAGQBDUV Indoor and outdoor installation Central tube with 2 glassfibre rods for

increased tensile strength

Fibre Ribbon

Water swelling yarn Halogen-free flame protected sheath

Fire protection class F4C

Dry fibre-optical combined cable for indoorinstallation and outdoor installation in ducts. Thecable complies with fire requirements under IEC60332-3, cat C which corresponds with firepropagation class F4C according to SS 424 1475.


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Appendix 4 - Fibre optical cable for aerial installation

GARLCV Outdoor installation aerial normal span

70 meter

Polyester Central tube with optical fillingcompound Steel wire for strain relief

Halogen free polyethylene sheath

Fibre optical cable with metallic suspensioncable for aerial installation. There are well-tested techniques for end strain relief andintermediate suspension.

GRGLDV 4-12 fibres Outdoor installation, aerial or in ducts Polyester central tube with optical filling

compound Loose fibres

Aramid yarn for increased tensile strength

Polyethylene sheathMetal-free aerial optical cable for spans of up to50 metre. There are well-tested techniques forend strain relief and intermediate suspension.This design can also be blown through opticalducts.

GRSSLLDV Aerial outdoor installation

Slotted core with glass fibre rod as thecentre element

Polyester tubes with optical filling

compound Optical filling compound for lengthways

water tightness

Aramid yarn for strain relief

Double polyethylene sheaths

Fibre optical cable for installation aerial. Thecable type is intended for use with power linesof lower voltage than 55 kV and not morethan 12 kN tensile load.

There are well-tested techniques for end strainrelief and intermediate suspension.Please refer to the installation manual for moreinformation.

Optical cable system for aerial cables Max 55kV.


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Appendix 5 - Stations

Large station for handling a large number of fibres

The facility to handle a large number of fibres

is needed in some urban environments.Nexans have the passive components neededto construct all types of fibre installations instations.

Nexans N3S-system for a large number of fibres

in the station environment is shown below.

Nexans N3S system

The optical distribution frame (ODF), splicingframe, splicing module, patching frame,patching modules and a complete solution formanagement of cable harnesses and cables.Frames are available in several alternativeheights. Two of these are 2200x600x300 mm

and 2000x600x300 mm. Each maindistribution frame is equipped with a built-incable ladder for the harnesses. Cables areinstalled on ladders installed in the maindistribution rooms. The distribution boxes,which are pre-terminated, are available inthree sizes, 48, 96 or 192 fibres. The splicingmodule consists of 8 fold-out cassettes. 96fibres can be joined in each cassette (12divisible 8 fibre ribbons).For more information, please contact NexansIKO Sweden AB.

Capacity in patching frame:Height 2200 mm: Each frame can manage1536 SC terminals or 3072 MU or LC terminals.Height 2000 mm: Each frame can manage1344 SC terminals or 2688 MU or LC terminals.

Capacity in splicing frame:Height 2200 mm: Each frame can manage7680 fibre joints with 8 fibre ribbons.Height 2200 mm: Each frame can manage3840 fibre joints with loose fibres.Height 2000 mm: Each frame can manage6912 fibre joints with 8 fibre ribbons.Height 2000 mm: Each frame can manage3456 fibre joints med loose fibres.

From front Rear Pulled out ODF


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Smaller stations

In smaller stations, where a lower number offibres will be handled, traditional framesolutions can be used (unless you are

building for future density increase, in thatcase, a compact multi-fibre (high fibre count)system should be used).

This means that a frame or box is installed atthe station, which is used for patching, cablemanagement, active equipment and anyjoints.

The patching field can be arranged on site,using loose components where you weld thefibre tails or fan-outs yourself and install themin the box. The patching field can also be

purchased pre-terminated, where all theterminations are installed at the factory,

Pre-terminated patching fields are availablein the following sizes: 12, 24, 48, 96 or 192fibres.

Examples of accessories unitwise

Patching field, KB112

Cable guide Adapters

Pigtail Fan-out Cassette/

joint holder

There is an optional strain relief kit for microcables or micro tubes for the KB112 .This makes it possible to take in and terminateand/or join up to 12 cables/tubes containing atotal of 48 fibres.

Strain relief kit for 12 cables/tubes

Pre-terminated patching field, KB112

Floor cabinet, Quick Mount


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Appendix 6 Fibre optical splice boxes

For robust fibre optical cable

Fibre optical splice boxes are used for joiningfibre optical cables. Nexans splicing closure

system includes several solutions, dependingon cable type, number of fibres andapplication. When robust cable is used, alarge number of fibres (48-384) are ofteninstalled between the station and the junctionpoints.

In the junction point, the desired number offibres is branched out and the other fibrescontinue to the next junction box. The fibreswhich are branched out continue in cables withfewer fibres (2-24), depending on what the

cable is going to be connected to. 2-4 fibres arefrequently installed to a private house and 12-24 fibres can be a good choice for anapartment block.

For fibre optical micro cable

Nexans splicing closure system is designed tobe able to handle just a few or many fibres atthe same time, where the fibres can emergefrom several cables of different diameters. Inpractice, this means that all splice closures canbe provided with mechanically sealed

inlets/outlets for up to 72 cables of diameter2-27 mm and handle up to 1200 fibres.

For fibre optical aerial cable

Nexans have developed a construction systemfor aerial installation. The system is complete,

with all products from station to customer,containing cables, junction boxes, strain reliefand suspension devices, plus ready-terminated products.

All Nexans splice closures are available witha patching fields.

Example of splice closures with patching field.

Example of cable gland for micro cable


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WTC0.5Fibre optical junction box, type WTC0.5 isintended for installation in a manhole or on apole. WTC0.5 has 2 separate cable inputs.These inputs can be provided with

mechanical glands for 1-12 cables (max 24),depending on cable diameter(2-27 mm).

WTC2WTC2 fibre optical junction box intended forinstallation in a manhole or on a pole. WTC2has 6 separate cable inputs. These inputs can beprovided with mechanical glands for 1-12 cables

(max 72) depending on cable diameter (2-27mm).

WTC1Fibre optical junction box, type WTC1intended for installation in a manhole or on a

pole. WTC1 has 4 separate cable inputs.These inputs can be provided withmechanical glands for 1-12 cables (max 48),depending on cable diameter(2-27 mm).

DSCFibre optical junction box, type DSC intended forinstallation in a manhole. DSC has 6 separate

cable inputs. These inputs can be provided withmechanical glands for 1-12 cables (max 72),depending on cable diameter (2-27 mm).


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Accessories

All Nexans fibre optical splice closures areprovided with mechanical glands for allconnected cables. This means that no heat

shrink material is used. This preventsinvoluntary damage to fibres and cables dueto application of heat.

To help you, Nexans have prepared a number ofbasic configurations where a pre-determinednumber of cables and a fixed number of fibres

can be connected. These items can of course besupplemented to suit other configurations.


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Appendix 7 Fibre optical joint and termination cabinet for wall installation

Cros Micropticable

Fibre optical wall cabinet for joining up to 48

fibres, but also supports termination of up to12 fibres (SC connectors). Cros Micropticablewall cabinets are intended for use as fibrejunction points by installing them in thebasement etc. From this point, 1-12 fibrescan be terminated in active equipment ordirect to the customer.

The wall cabinet has a mid span input and isprepared to support micro-ducting and/ormicro cables such as Nexans Micropticable.The wall cabinet is supplied complete withcable anchorages, panel plate and cassettes.

Please ask Nexans about other material.

Cros UTC

Fibre optical wall cabinet for splicing up to 96

fibres. Cros UTC wall cabinets are intended foruse as fibre junction points by installing them inthe basement etc. From this point, up to 36cables can be run straight to customers.

The wall cabinet has a mid span input and isprepared to support micro-ducting and/ormicro cables such as Nexans Micropticable.The wall cabinet is supplied complete withcable anchorings and cassettes.


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Cros Plus I

Fibre optical wall cabinet for splicing up to 96fibres, but also supports termination of up to48 fibres (SC connectors). Cros Micropticable

wall cabinets are intended for use as fibrejunction points by installing them in thebasement etc. From this point, up to 48 fibrescan be terminated in active equipment ordirect to the customer.

The wall cabinet has a mid span input and isprepared to support micro-ducting and/ormicro cables such as Nexans Micropticable.The wall cabinet is supplied complete withcable anchorages, panel plate and cassettes.Please ask Nexans about other material.


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Appendix 8 Fibre optical customer termination unit for wall mounting

Cros Premium

Compact fibre optical wall cabinet

(345x240x45 mm) for termination of up to12 fibres (SC connectors).

Cros Premium wall cabinets are intended foruse as the interface between the operator andthe customer. Cros Premium cabinets can belocked with two different key systems forcustomer/operator.

Customer terminal

Pre-terminated fibre-optical customer

termination unit for installation in an apartmentor private house. Contains 2 or 4 fibre-opticalSC connectors.

Customer termination units are supplied for usewith the following types of cable: GAGQBDUV,TB or Nexans Micropticable range UT, UB orMB.


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Appendix 10 - Other material

A considerable amount of other material andtools are needed to construct a complete fibreoptical network, such as cutting and stripping

tools, cleaning products and fibre opticalpatch cables. These products and many moreare included in Nexans product range.


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DESCRIPTION-3waystoconstructFibre-To-The-HomeNov2005Nexans

3 ways to construct fibre-to-the-home

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