Part270_Telecommunications_Cabling by keralaguest

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									Edition: February 2008                                                 Specification: Part 270 Telecommunications Cabling

                                                        PART 270

                                       TELECOMMUNICATIONS CABLING


CONTENTS

1.          General
2.          Supply of Telecommunications Cabling
3.          Installation of Telecommunications Cables
4.          Testing and Commissioning
5.          Signal Grounding System
6.          "As Built" Documentation
7.          Hold Points
8.          Verification Requirements and Records

1.          GENERAL

This Part specifies the requirements for the supply and installation of telecommunications cabling used for Intelligent
Transport Systems (ITS). This Part shall be read in conjunction with Part 260 “General Requirements for the Supply
of ITS Equipment” and if installation forms part of this Contract, Part 261 “Installation of ITS Equipment”.

Note: a reference in this Part to a clause in Part 260 “Supply of ITS Equipment” is indicated by “260.” preceding the
clause number.

2.          SUPPLY OF TELECOMMUNICATIONS CABLING

2.1         Twisted - Pair Copper Cables

LAN Cables

Twisted-pair cables intended for Local Area Networks shall:
      (a)       Have a characteristic impedance (Zo) of 100 ;
      (b)       Be screened;
      (c)       Non-armoured;
      (d)       Not less than 4 twisted pairs; and
      (e)       Comply with current ACA regulatory requirements.

Co-axial Cables

Co-axial cables shall have a 75  characteristic impedance (Zo) and incorporate a solid polyethylene dielectric and
at least a 93% copper (single) braid coverage. It shall have an environmental operating temperature range of –40°C
to 80°C and a nominal attenuation of less than 0.33 dB @ 1 GHz.

Co-axial Cable Connectors

Co-axial cable connectors shall comply with the following specifications:
      (a)       Have a return loss of greater than 26 dB;
      (b)       A characteristic impedance (Zo) of 75 ;
      (c)       Have crimped inner/outer conductor connections; and
      (d)       Where coaxial connectors/cables are placed in environmental service, connections shall be treated with
                a rubber-based, pressure sensitive, moisture-tight adhesive wrapping tape.




DPTI XXCxxx                                                                                                       Page 1
Edition: February 2008                                                  Specification: Part 270 Telecommunications Cabling


Composite Cables

Composite cables comprising power, co-axial and control cables within the same sheath shall be used for connection
between camera Equipment on a camera mast and the associated field cabinet.

Copper Communications Cable Joints

Copper Communications cable joints in pits shall be suitable for underground installation, utilise Insulation
Displacement Connectors (IDC) and have an open-able waterproof seal. All joints shall be purpose-made and
installed in accordance with the manufacturer's instructions.

The Contractor shall be suitably trained in such jointing techniques.

2.2         Optical Fibre Cables

Multi-mode Cable

All multi-mode optical fibre cables shall be non-armoured and meet the following requirements:
      (a)       Conform to ITU Recommendation G.651;
      (b)       Core diameter - 62.5 m;
      (c)       Cladding diameter – 125 m;
      (d)       Coating diameter – 250 m;
      (e)       Fibres shall be enclosed by a silicone or other approved composite resin material enclosed within
                colour-coded loose tubes formed around a central strength member. Solid polyethylene fillers shall
                form part of the cable to produce a circular cable and each fibre within a tube shall be individually
                coloured;
      (f)       Maximum attenuation of 3.2 dB/km @ 850 nm;
      (g)       Maximum attenuation of 1.0 dB/km @ 1 310 nm;
      (h)       Not less than 200 MHz transmission bandwidth @ 850 nm;
      (i)       Not less than 500 MHz transmission bandwidth @ 1 310 nm; and
      (j)       0.275 m Numerical Aperture.

Single-mode Cable

All single-mode optical fibre cables shall be non-armoured and meet the following requirements:
      (a)       Conform to ITU Recommendation G.652;
      (b)       Core diameter – 9 m;
      (c)       Cladding diameter – 125 m;
      (d)       Coating diameter – 250 m;
      (e)       Fibres shall be enclosed by a silicone or other approved composite resin material enclosed within
                colour coded loose tubes formed around a non-metallic central strength member. Solid polyethylene
                fillers shall form part of the cable to produce a circular cable and each fibre within a tube shall be
                individually coloured. Each loose tube shall contain 6 fibres;
      (f)       Maximum attenuation per kilometre at 1 310 nm optical frequency - 0.4 dB/km; and
      (g)       Maximum attenuation per kilometre at 1 550 nm optical frequency - 0.3 dB/km.




DPTI XXCxxx                                                                                                        Page 2
Edition: February 2008                                                    Specification: Part 270 Telecommunications Cabling

Splice Panels

Optical Fibre Splice Panels shall meet the following requirements:
    (a)       19" rack mountable;
    (b)       Splice protection and pigtail storage;
    (c)       Suitable for housing fusion splices;
    (d)       Rear or side cable entry; and
    (e)       Integral sliding splice trays.

Optical Fibre Patch Panels shall meet the following requirements:
    (a)       19" rack mountable;
    (b)       Integral SC patch panel;
    (c)       Complete with factory installed multi-fibre intra-facility cable, cable clamp and retainers; and
    (d)       Swing out bulkhead for access to rear of patch panel.

Combined Optical Fibre Splice/Patch Panels shall meet the following requirements:
    (a)       19" Rack Mountable;
    (b)       Integral sliding splice tray and SC patch panel;
    (c)       Suitable for loose tube and riser cable installation; and
    (d)       Rear or side cable entry.

Optical Fibre Connectors and Pigtails

All ST/SC connectors shall be guaranteed for a minimum of 500 operations and all unused optical connectors shall
have dust caps fitted. ST shall be used only where the connected Equipment requires ST connectors, all other
connector shall be SC type. Maximum insertion loss shall be less than 0.4 dB, a return loss of greater than 85 dB
and an environmental operating temperature range of –40C to 85C.

Connectors shall be used for terminating optical fibre cable to Equipment and Optical Fibre patch panels. All optical
fibre connectors used for pigtails and patch leads shall be SC (preferred) or ST type factory fitted to a reinforced
fibre tail with return loss less than –50 dB and insertion loss less than 0.5 dB.

Pigtails shall be 2 m in length. Patch leads shall be minimum 2 m in length. The Contractor shall provide optical
fibre patch leads to allow the looping of all unused fibre optic patch connections.

Optical Fibre Cable Joints and Splices

All joints shall use fusion splices, splice protectors and be held in a purpose made splice organiser. Joints shall be
installed in accordance with the manufacturer's instructions. Splices made within field cabinets shall be housed
within a hermetically sealed box containing silica gel to prevent damage from moisture.

Splices shall have an insertion loss of 0.2 dB or less.

All splicing shall be carried out in strict accordance with the cable manufacturer's and splicer manufacturer's
instructions. The Contractor shall be suitably trained in such jointing techniques.

In pits, optical fibre cable housings shall be suitable for underground installation and have an open-able waterproof
seal.




DPTI XXCxxx                                                                                                          Page 3
Edition: February 2008                                                 Specification: Part 270 Telecommunications Cabling

3.       INSTALLATION OF TELECOMMUNICATIONS CABLES

This Clause provides additional requirements to those of Part 261 “Installation of ITS Equipment”.

Telecommunications cables shall be installed as a continuous run and shall be enclosed by conduit throughout. The
conduit routes and cable routes to be utilised shall be as shown on the Drawings.

The Contractor shall confirm that the conduits are suitable for cable installation prior to hauling the cable. The
Contractor shall provide a polypropylene or equivalent rot-proof draw cord of 5 kN breaking load in each conduit on
completion of cable installation. Draw cord ends shall be secured within the pits to which the conduit is terminated.

No cables shall be left exposed at the end of any work period. In the event of any cables being vandalised or stolen,
the cable shall be replaced with an equal length of unbroken cable. In the event of any cable damage during
installation the whole of the particular length of cable concerned shall be removed, replaced and re-connected at the
Contractor's expense prior to system commissioning.

The Contractor shall identify all cables with a cable number applied via the "Grafoplast" cable marking system
utilising black lettering on a white background at all jointing and termination points. In addition cables shall be
labelled where they pass through drawpits. For copper cables all unused cores shall be clearly identified (i.e. with
cable number) and terminated with each core occupying a separate terminal. For backbone optical fibre cable all
unused cores shall be spliced through end to end. For spur optical fibre cables each unused core shall be coiled
within a fibre splice cassette in the joint and rack mounted termination panel. Cables shall be labelled immediately
following installation. All optical fibre and copper communications cable cores shall be suitably labelled within
joints and termination panels.

The length of optical fibre cable to be installed between splices shall be not less than 2 000 m.

The draw cord shall not be used for hauling the cable but shall be used to pull through a purpose-made cable hauling
rope. The cable hauling rope shall be attached to the cable by means of a hauling eye fitted to the central strength
member of the cable in the case of optical fibre or to a stocking in the case of copper cables. The Contractor shall
attach a swivel between the cable hauling rope and the hauling eye.

Cables shall be installed using a dynamic mechanical winch fitted with a clutch. Bell mouths shall be fitted to the
entry and exit of every conduit, including intermediate points, prior to the commencement of cable installation.

Where intermediate pits exist in the cable route the cable shall be installed through each chamber in one operation.
Cable guides shall be used to support the cables in all intermediate pits.

The Contractor shall ensure that all cables are lubricated during installation using an approved water based
biodegradable lubricant.

Sufficient length of cable shall be allowed for correct termination. Cables shall be sealed against the ingress of
moisture when termination does not proceed immediately following installation.

Cables shall not be bent to an internal radius of less than 25 times the external diameter of the Optical Fibre cable,
and not to less than six times the external diameter of the cable for copper, or less than the radius recommended by
the manufacturer, whichever is greater.
Where optical fibre breakout is required, only the fibre cores to be spurred off shall be jointed. All other cores shall
remain intact.

All cables exceeding 50 m in length shall be provided with 5 m re-termination loops at all joint and termination
points. These loops shall be installed at each end of the cable in a pit adjacent the field cabinet or at a joint pit as
applicable. All cables entering a control room or building shall also be provided with 5 m re-termination loops to be
installed under the floor in the Communications Room or, where this is not possible in the nearest joint pit.

In addition all cable runs shall be provided with a 5 m cable loop nominally every 500 m, to be coiled within a joint
pit.




DPTI XXCxxx                                                                                                          Page 4
Edition: February 2008                                                   Specification: Part 270 Telecommunications Cabling

4.          TESTING AND COMMISSIONING

4.1         General

Prior to testing, the Contractor shall demonstrate the correct functioning and current calibration of all test
Equipment.

The Contractor shall provide at least 48 hours notice of the time and date that each stage of the testing will be
undertaken. Provision of the notification shall constitute a HOLD POINT.

The results shall be submitted within 5 working days of tests being concluded.

4.2         Stages of Cable Testing

The testing of cables shall be carried out in 3 stages.

Each cable shall have passed Stage 1 testing prior to the interconnection with other cables.

Stage 2 tests shall be carried out both on completed sections of backbone optical fibre cable and copper
communications cable sections. Stage 2 tests shall be satisfactorily completed before the connection of spur cables
to the communications backbone.

Stage 3 tests shall be carried out following the successful completion of Stage 2 testing and the connection of spur
cables and pigtails. Equipment shall not be connected to the communications backbone before Stage 3 testing of the
relevant link has been successfully completed.

Any failure or abnormality during cable testing shall be reported.

4.3         Stage 1 Testing

The Contractor shall test the basis continuity (electrical and optical) of all cables.

Following the installation of Optical Fibre, each core length shall be tested using an Optical Time Differential
Reflectometer (OTDR).

For metallic cables, a "General Purpose" test set (or similar) shall be used to prove continuity for metallic cable plant
including coaxial cables.

The Contractor shall test the continuity of each core of a copper communications cable immediately following
installation.

These tests shall be sufficient to reveal any crossed pairs, open circuits any significant mismatches.

4.4         Stage 2 Testing

(1)         Optical Fibre Cables

The Contractor shall test the completed optical fibre backbone cable section including splices and through
connectors in both directions using an OTDR at both 1 310 nm and 1 550 nm optical wavelengths. The test shall be
carried out prior to any jointing of optical fibre spur cable to the backbone.

The Contractor shall record the following results:
      (a)       Length of fibre (metres);
      (b)       Attenuation of fibre (dB/km);
      (c)       Loss of splice (dB); and
      (d)       Location of splice(s) (m).

The cable shall not be accepted if the difference between end-to-end attenuation exceeds 0.5 dB/km for any fibre
core.


DPTI XXCxxx                                                                                                         Page 5
Edition: February 2008                                                  Specification: Part 270 Telecommunications Cabling


(2)         Copper Cables

The Contractor shall carry out the following tests after completion of installation and jointing of copper
communications cables:
      (a)       Continuity tests on all copper conductors to check there are no "shorts", "opens" or transitions. The
                Contractor shall rectify any failures prior to commencement of the remaining tests;
      (b)       The loop resistance for each pair shall be measured using a "GP", Lines test set (or similar) and
                appropriately recorded; and
      (c)       Insulation Resistance (IR) tests shall be carried out using a Megger (or similar) and measurements shall
                not be less than 10 M (at 20C) at 250V DC after one minute. IR tests are applied between "A" and
                "B" legs and between "A" and "B" and Earth respectively).

4.5         Stage 3 Testing

The Contractor shall carry out Stage 3 testing during the connection of spur cables and pigtails to the Optical Fibre
backbone. Tests shall be carried out to confirm the integrity of any splices or connections made and shall be
undertaken end to end between Equipment locations using an OTDR at both 1 310 mm and 550 mm optical
wavelengths.

The Contractor shall record the following results:
      (a)       Length of fibre (metres);
      (b)       Attenuation of fibre (dB/km);
      (c)       Loss of splice/connector (dB); and
      (d)       Location of splice(s)/connector(s) (metres).

The cable shall not be accepted if the end-to-end differential exceeds 0.5 dB/km for any core, or if the attenuation of
any connector and pigtail exceeds 0.5 dB measured as insertion loss.

5.          SIGNAL GROUNDING SYSTEM

5.1         General

A Signal Grounding System shall be provided so as to minimise the possibility of earth currents inducing electrical
noise into data, video and other sensitive circuits.

DC power supplies within the ITS system shall be electrically isolated from and not referenced to the main supply
earthing system. The 0-Volt connection or return current shall not be connected to earth potential.

5.2         Compliance

The Signal Grounding System employed at ITS communications facilities shall comply with objectives of ACA
Standard TS009-1996.

5.3         Communications Earth System (CES)

The Signal Grounding System methodology used forITS telecommunications installations shall be known as a
Communications Earth System (CES).

Earth cables used for the CES shall have Green/Yellow banded insulation. The resistance of the Earth conductor
between the point of connection and the protective Earth System and the Earth Bar at the Building Distributor (or
equivalent) shall not exceed 1 Ohm.




DPTI XXCxxx                                                                                                         Page 6
Edition: February 2008                                               Specification: Part 270 Telecommunications Cabling

6.          "AS BUILT" DOCUMENTATION

Further to Clause 260.14 “As Built Documentation”, the drawings, diagrams and circuits of the actual installation
shall include the following information:
      (a)     Location and depth of Service Trenches, containing ITS infrastructure;
      (b)     Layout of and size of ITS conduits and pits (ITS Communication Pit and Pipe);
      (c)     Capacity and type of power cables including communication cables used for ITS purposes;
      (d)     Location and designation of Field Cabinets;
      (e)     Location of Earth Points including the measured earth resistances; and
      (f)     Cable termination and testing results including OTDR test results.

7.          HOLD POINTS

The following is a summary of Hold Points, vide Part 140 "Quality System Requirements", referenced in this Part:

     CLAUSE                                                                                           RESPONSE
                                                 HOLD POINT
      REF.                                                                                              TIME
        4.1       Notification of testing                                                           48 hours


8.          VERIFICATION REQUIREMENTS AND RECORDS

The Contractor shall supply the following records:


     CLAUSE
                SUBJECT                       RECORD TO BE PROVIDED
      REF.

        4       Testing and commissioning     Stage 1, 2 & 3 Test Records

     260.12     Warranty                      Manufacturer’s Warranty

      6 and     System documentation          “As Built” documentation
     260.14




                                                     ____________




DPTI XXCxxx                                                                                                     Page 7
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