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DOCUMENT CONTROL

Document Owner

Name: Mark Van Vuuren

Position: Field Practices Coordinator

Date: March 2013

Approved By *

Name: Mark Van Vuuren

Position: Field Practices Coordinator

Date: March 2013

Authorisation **

Name: Lance Roberts

Position: Manager Safety and Health

Date: March 2013

Date Created/Last Updated March 2013 / October 2018

Review Frequency *** Every 3 years

Next Review Date *** October 2021

* Must be the Process Owner and is the person assigned authority and responsibility for managing the whole process, end-

to-end, which may extend across more than one division and/or functions, in order to deliver agreed business results. The Process Owner can also be the Document Owner.

** This person will have the power to grant the process owner the authority and responsibility to manage the process from end

to end.

*** Frequency period is dependent upon circumstances – maximum is 5 years from last issue, review, or revision whichever is

the latest. If left blank, the default will be 1 year unless otherwise specified.

STAKEHOLDERS

The following positions must be consulted if an update or review is required:

NOTIFICATION LIST

The following positions must be notified of any authorised change:

Manager - Safety & Health Manager - Safety and Health

Asset Managers - Operations Manager - Engineering & Projects Services

Fields Practices Coordinator Fields Practices Coordinator

Works Delivery Managers Regional Management Teams (RM, AM, ASM/WDD)

Asset Services Managers Operational Staff

Copyright 2012 - Copyright is owned by Horizon Power (ACN 57 955 011 697). All rights reserved. No part of this work may be reproduced or copied in any form or by any means (graphic,

electronic, taping or information retrieval system) without the written permission of the copyright owner.


Important Notice to Users

This Underground Cable Installation Manual has been developed for use by Horizon Power employees’ and Contractors, engaged to perform construction and maintenance work on Horizon Powers’ underground electrical distribution networks.

The manual provides guidelines for a minimum acceptable standard of underground construction that is required by Horizon Power. To this end, this manual provides the framework by which auditing of the underground electricity distribution network may be undertaken.

It is issued by as a controlled document by Horizon Power to Horizon Power employees’ and Contractors on the condition that it will only be used whilst undertaking underground cable installation work on Horizon Power underground electrical distribution networks. Underground cable installation work will only be performed by individuals who are appropriately trained and qualified in accordance with accepted standards within Horizon Power. This Manual is not intended, and should not in any way be relied upon, as a substitute for such training.

Hierarchy of Documentation

WA general workplace safety legislation administered by the regulator WorkSafe WA:

Occupational Safety and Health Act 1984

Occupational Safety and Health Regulations 1996

WA Electrical legislation administered by the regulator EnergySafety WA:

Electricity Act 1945

Electricity Licencing Regulations 1991

Electricity Regulations 1947

An illustration of the hierarchy of documentation can be seen below.

In the interest of your own personal safety, and the safety of all Horizon Power workers, contractors and the general public it is essential that you read these standards and understand how they relate to your work environment.

These Standards will be regularly reviewed, if there are any queries and suggestions for improvement, then direct your queries to the Field Practices team via the Continuous Improvement Process


Acts & Regulations

Codes of Practice

AS/ANZ Standards

Guidenace Notes

Horizon Power Safety & Health Management

Systems

Horizon Power Electrical Safety

Standards

Horizon Power Work Instructions

Horizon Power Switching Manuals

Horizon Power published technical

standards & guidelines

Figure 1 – Illustration of the hierarchy of documentation

Last review: October 2018 DM#

Table of Contents

Section Section Number

1 PURPOSE ............................................................................................................1-4

2 SCOPE .................................................................................................................2-4

3 DEFINITIONS AND REFERENCES .....................................................................3-5

3.1 Definitions ................................................................................................................. 3-5 3.2 References ................................................................................................................ 3-7

4 GENERAL REQUIREMENTS ...............................................................................4-8

4.1 Training and Authorisation ......................................................................................... 4-8 4.2 Job Planning and Risk Assessments (Work Planning) .............................................. 4-8 4.3 Personal Protective Equipment (PPE) ....................................................................... 4-9 4.4 Contractor Responsibilities ........................................................................................ 4-9 4.5 Traffic Management .................................................................................................. 4-9 4.6 Instructions, Procedures and Standards .................................................................. 4-10

5 SURVEYING AND “AS CONSTRUCTED” RECORDS ..................................... 5-11

5.1 Survey Benchmarks and Datum Points ................................................................... 5-11 5.2 As Constructed Records .......................................................................................... 5-11

6 CROSSINGS....................................................................................................... 6-12

6.1 Railway Crossings ................................................................................................... 6-12 6.1.1 Planning Requirements ........................................................................................... 6-12 6.1.2 Installation of Cables and Conduits ......................................................................... 6-12 6.1.3 Installation of Cable Location Markers ..................................................................... 6-12 6.1.4 Installation of Power Cables under tracks and elsewhere on railway property ......... 6-13 6.2 Existing Pipes or Cables .......................................................................................... 6-15 6.3 Gas Mains ............................................................................................................... 6-16 6.4 Communications...................................................................................................... 6-16 6.5 Existing Underground Electrical Cables ................................................................... 6-16 6.6 Road and Vehicle Crossings ................................................................................... 6-17 6.7 Horizontal Cable Clearance to other Services at Road Crossings ........................... 6-17

7 CABLE TUNNELS AND SUPPORT SYSTEMS ...................................................7-1

7.1 General ..................................................................................................................... 7-1 7.2 Access Pits ................................................................................................................ 7-1 7.3 Cable Support ........................................................................................................... 7-1

8 CABLE ON AND OFF “NORMAL” ALIGNMENT ................................................8-2

8.1 Standard Cable Alignment ......................................................................................... 8-2 8.2 Alternative Cable Alignment ...................................................................................... 8-2 8.3 Easements ................................................................................................................ 8-2 8.4 Retrospective Undergrounding .................................................................................. 8-3


9 TRENCHING AND EXCAVATION ....................................................................... 9-1

9.1 General ..................................................................................................................... 9-1 9.2 Blasting ..................................................................................................................... 9-1 9.3 Excavated Materials .................................................................................................. 9-1

10 DIRECTIONAL DRILLING .......................................................................... 10-2

10.1 Installation Principles ............................................................................................... 10-2 10.2 Drilling ..................................................................................................................... 10-3 10.3 Drilling Fluids Management Plan ............................................................................. 10-3

11 PLOUGHING ............................................................................................... 11-4

12 CABLE LAYING .......................................................................................... 12-6

12.1 Drum Mounting and Inspection ................................................................................ 12-6 12.1.1 Inspection prior to installation: ................................................................................. 12-6 12.1.2 Preparation for installation ....................................................................................... 12-6 12.2 Protection of Cables during Installation ................................................................... 12-7 12.3 Cable Installation methods ...................................................................................... 12-7 12.3.1 Stocking Pulling ....................................................................................................... 12-7 12.3.2 Installation using Pulling Eyes ................................................................................. 12-7 12.3.3 Bond Pulling ............................................................................................................ 12-8 12.3.4 Armour Pulling ......................................................................................................... 12-8 12.3.5 Mechanical Assisted Installation .............................................................................. 12-8 12.4 Cable Pulling Tensions ............................................................................................ 12-8 12.5 Pulling Speed .......................................................................................................... 12-9 12.6 Cable Bending Radii ................................................................................................ 12-9 12.7 Maximum Number of Cable Joints ........................................................................... 12-9 12.8 Installation of Cables on Poles ................................................................................ 12-9 12.9 Bedding and Backfill ................................................................................................ 12-9 12.10 Depth of Cover for Cables ....................................................................................... 12-9 12.11 Cable Protection Covers and Marker Tapes .......................................................... 12-10 12.12 Sealing of Cables .................................................................................................. 12-10

13 CONDUITS ................................................................................................ 13-10

13.1 Application ............................................................................................................ 13-10 13.2 Requirements for cables installed outside normal alignments ............................... 13-11 13.3 Encased Conduits ................................................................................................. 13-11 13.4 Sealing of Conduits ............................................................................................... 13-11 13.5 Installation requirements for Conduits ................................................................... 13-11 13.6 Pulling Cables through Conduits ........................................................................... 13-12

14 CABLE JOINTING AND TERMINATIONS .................................................... 13

14.1 General ...................................................................................................................... 13 14.2 Cable Joint Excavations ............................................................................................. 13 14.3 Jointing ....................................................................................................................... 14 14.4 Termite Proofing ......................................................................................................... 15 14.5 Terminations .............................................................................................................. 15 14.6 Working Ends ............................................................................................................. 16

15 TESTING AND COMMISSIONING ................................................................ 16


16 REINSTATEMENT ......................................................................................... 17

16.1 General ...................................................................................................................... 17 16.2 Compaction ................................................................................................................ 17 16.3 Levelling ..................................................................................................................... 17 16.4 Restoration of Surface ................................................................................................ 18

17 DAMAGE TO PROPERTY ............................................................................. 18

17.1 General ...................................................................................................................... 18

18 PILLARS AND PITS ....................................................................................... 19

18.1 General ...................................................................................................................... 19

APPENDIX A - SERVICE ALIGNMENT, DEPTH AND COLOURS FOR GREENFIELD SITE .............................................................................................................................. 20

APPENDIX B – CABLE INSTALLATION DATA .......................................................... 21

APPENDIX C - DIAL BEFORE YOU DIG SERVICE .................................................... 21


1 PURPOSE

This manual specifies the technical requirements for the safe and efficient installation of underground cables on Horizon Power’s electrical distribution networks, which provides the minimum requirements for:

All Horizon Power workers who work in and around excavations.

All Horizon Power workers how undertake directional drilling.

All Horizon Power workers engaged in installing underground cables.

Any process that displaces soil.

This document refers to other Horizon Power documents to provide reference standards for underground cable installation work.

2 SCOPE

This manual has been developed for use by Horizon Power workers’ and Service Providers engaged in the installation of high and low voltage distribution cables on the Horizon Power electrical networks.

Horizon Power workers’ and Service Providers shall comply with these requirements, except as otherwise approved.

For subdivisional work managed by a developer where the subdivision does not require equipment to be installed on public land, some items in this document may not be applicable as they are specified in the Underground Distribution Scheme (UDS) Manual.

Note: Public land is land that at the time of subdivision is freely available for public use, e.g., existing road reserves, Public Access Way (PAW), Public Open Space (POS) etc.


3 DEFINITIONS AND REFERENCES

3.1 Definitions

Accredited Service Provider (ASP)

A person or an entity who has been accredited through the accreditation scheme of Horizon Power to undertake any construction work on Horizon Power underground network.

Approved Appropriate organisation endorsement in writing for a specific function.

Authorised Person

A person with technical knowledge or sufficient experience who has been approved or delegated authority to act on behalf of Horizon Power to perform the duty concerned.

Cable A single cable core, or two or more cable cores laid up together, either with or without fillings, reinforcements or protective coverings.

Conductor A wire or other form of conducting material suitable for carrying current, but not including wire or other metallic parts directly employed in converting electrical energy into another form.

Construction Project Manager (CPM)

The officer appointed by Horizon Power as Horizon Power’s representative to whom all site contractual and technical matters are referred.

Earthed Directly electrically connected to the general mass of earth so as to ensure and maintain the effective dissipation of electrical energy.

Energised Connected to a source of electrical supply.

High voltage A nominal voltage exceeding 1,000 V ac or exceeding 1,500 V dc.

Insulated Separated from adjacent conducting material by a non-conducting substance or airspace permanently providing resistance to the passage of current, or to disruptive discharges through or over the surface of the substance or space, to obviate danger of shock or injurious leakage of current.

Live Energised or subject to hazardous induced or capacitive voltages.

Low voltage Nominal voltage exceeding 50 V ac or 120 V dc but not exceeding 1000 V ac or 1500 V dc.

Safe Not posing an unacceptable risk to life, health or property.


Safety Observer A person competent for the task and specifically assigned the

duty of observing and warning against unsafe approach to electrical apparatus, or other unsafe conditions.

Shall A requirement is "mandatory”.

Should A requirement Is "advisory or discretionary”.

Voltage A potential difference between conductors or between conductors and earth.

HDPE High Density Polyethylene

HV High Voltage

LV Low Voltage

MRWA Main Roads Western Australia

PTA Public Transport Authority

PAW Public Access Way

POS Public Open Space

UDS Manual Underground Distribution Schemes Manual

WAGR Western Australian Government Railway

WAPC Western Australian Planning Commission

XLPE Cross-linked Polyethylene


3.2 References

Requirements and Information relating to this manual may be found within the source documents detailed below:

Utility Providers Code of Practice, Main Roads WA;

Restoration and Reinstatement Specification for Local Governments in Western Australia published by the Institute of Public Works Engineering Australia (available from Main Roads WA’s web site);

Horizon Power Instruction Manual (HIM) Section 6, Underground Work

Horizon Power Underground Distribution Schemes (UDS) Manual;

Horizon Power Network Standard: Testing & Commissioning – Technical Requirements;

Dial Before You Dig Service for lodging an enquiry and requesting a plan;

Traffic Management for Works on Roads - Code of Practice, Main Roads WA;

Occupational Safety and Health Act 1984 and Occupational Safety and Health Regulations 1996.

WorkSafe Code of Practice: Excavation

Explosives and Dangerous Goods Act 1961 and Explosives and Dangerous Goods (Explosives) Regulations 1963;

AS 1742 Manual of uniform traffic control devices, Australian Standards;

AS/NZS 3000 – Australian/New Zealand Wiring Rules; and

AS 4799-2000 Installation of underground utility services and pipelines within railway boundaries.


4 GENERAL REQUIREMENTS

All Horizon Power underground cables shall be a termite protected type. Termite protection is critical to achieve 40+ year cable life, as Horizon Power cables are often installed in termite affected areas

Cables are termite protected using the following means:

a) inclusion of a termite protection in the outer sheath (Horizon Power method); b) double brass tapes; c) nylon sheaths

The cable sheath MUST NOT be scratched during installation. Scratch damage to the outer sheath may allow termites’ mandibles (pincers) to “bite” into the cable outer sheath.

4.1 Training and Authorisation

Underground Cable Installation work shall only be performed by individuals who are appropriately trained, qualified and authorised in accordance with accepted standards within Horizon Power.

Service Providers are responsible for ensuring all its employees’ and Sub-Contractor employees’ have been authorised by Horizon Power.

They must submit to Horizon Powers site representative confirmation of authorisation for each employee, prior to the commencement of the works.

Note: This Manual is not intended, and should not in any way be relied upon, as a substitute for training.

4.2 Job Planning and Risk Assessments (Work Planning)

Before the commencement of work, a risk assessment must be carried out using the Risk Analysis Procedure (OSH-3.6-1-02), to identify and document the hazards and risks associated with the task and ensure appropriate control measures are implemented.

It is important that, appropriate control measures must be identified, documented and implemented in order to control hazards to As Low as Reasonable Practicable (ALARP).

The on-site job risk assessment shall include but not limited to:

Identify and discuss the job hazards;

Assess the risks that may result because of the hazard;

Agree on the tasks assigned to control or remove the hazards & risks; and

Implement the control measures


4.3 Personal Protective Equipment (PPE)

Horizon Power Workers engaged in the installation of high and low voltage distribution cables on the Horizon Power electrical networks shall wear the Personal Protective Equipment (PPE) as required in accordance with Horizon power’s Instruction Manual:

FI 2.1 Glove Protection

FI 2.2 Head Protection

FI 2.5 Other Personal Protective Equipment

FI 2.6 Worksite Clothing/Personal Protective Equipment

4.4 Contractor Responsibilities

The Contractor is to provide competent, qualified and licensed Personnel to undertake Underground Cable Installation.

All Contractor Personnel utilised to carry out work activities on or near Horizon Powers electrical networks must have Horizon Power authorisation prior to the commencement of the Services, refer to Field Instruction Manual:

FI 1.2 Contractor Authorisation Process

FI 1.3 Construction site access – minimum requirements

4.5 Traffic Management

Horizon Power Workers shall ensure that where Services are sited adjacent to existing roads, adequate precautions are taken at all times to protect personnel, associated plant, and the general public.

Horizon Power Workers shall comply with the Main Roads Department Traffic Management for Road Works Code of Practice and Horizon Powers’ Network Instruction Manual:

FI 2.15 Temporary Safety Barriers and/or Warning Signs

FI 2.20 Traffic Management

The Local Government Authority shall be notified of any occasion it may be necessary to obstruct a road or footpath to carry out the Services.

Written consent shall be obtained from Main Roads Department and the relevant local authority before creating such obstruction.

All vehicles shall be fitted with suitable warning lights.


4.6 Instructions, Procedures and Standards

Horizon Power Workers and contractors shall comply with Horizon Power instructions, procedures, standards and construction drawings when engaged in the installation of high and low voltage distribution cables on the Horizon Power electrical networks.

This includes but not limited to the following Horizon Power documents:

Horizon Power Instruction Manual (HIM)

Electrical Safety Standards (ESS)

“Fit for Work” Policy

Hazard Incident Reporting Notification and Investigation Procedure

Working Near Horizon Powers’ Underground And Overhead Electrical Networks

Underground Distribution Schemes (UDS) Manual.

Underground Cable Installation Manual

Testing & Commissioning Standard

Substation Installation Manual

Distribution Equipment Labelling Standard

Horizon Power Construction Drawings


5 SURVEYING AND “AS CONSTRUCTED” RECORDS

5.1 Survey Benchmarks and Datum Points

There may be official survey benchmarks installed in the project work area. Precautions shall be taken to avoid disturbing these markers.

(Survey benchmark monuments are brass or metal disks in the ground. They measure exact horizontal positions (latitude and longitude) on the Earth because this

gives surveyors a point of reference)

Some benchmarks also measure elevations. These types of benchmarks indicate the height above or below sea level at that location.

Should any markers be disturbed, all costs associated with restoring the benchmarks to their correct position shall be borne by those responsible for such disturbance.

5.2 As Constructed Records

Upon completion of all work, the following “As Constructed” records shall be provided to the Horizon Powers’ Construction Project Manager (CPM):

1. Cable installation record. Where cables are installed using directional drilling, the length and depth of cables shall be recorded.

2. Electrical test schedules.

3. HV cable joint schedule.

4. Materials & equipment schedule.

The “As Constructed” records shall meet the requirements of Section 9.10.2 of the Underground Distribution Schemes Manual.

Standard forms for Electrical Test Schedules, HV Cable Joint Schedules and Materials & Equipment Schedule are available for download from Horizon Power’s web site.

https://gisgeography.com/latitude-longitude-coordinates/


6 CROSSINGS

6.1 Railway Crossings

If any works are proposed to be undertaken within or adjacent to rail reserves contact the relevant rail authority to obtain permission and compliance requirements

6.1.1 Planning Requirements

Before commencing any works associated with railway property, it is essential that all necessary applications are made and approvals obtained.

Details of the applications and approval process requirements are contained in the Utility Providers Code of Practice for Western Australia.

The approval process can take several months, so appropriate planning for the works is recommended.

In most cases, arrangements will be required to use a railway flagman at the site for the duration of the works.

6.1.2 Installation of Cables and Conduits

Where site conditions permit, the installation shall be by boring or directional drilling for the portion under the tracks and at least 3 m beyond the outer rails or 3 m beyond the toe of embankment, whichever is the further.

In the case of boring, the diameter of the bored hole shall not exceed the outside diameter of the pipe/conduit by more than 50 mm.

If the diameter of the bored hole exceeds the outside diameter of the pipe/conduit by 50 mm or the bored hole needs to be abandoned, the hole shall be backfilled and remedial measures shall be taken to provide support for the railway.

6.1.3 Installation of Cable Location Markers

Cable marker details are available in Horizon Power’s Distribution Design Catalogue (DDC) Section 7. Cable markers shall be installed to indicate the location of all underground power cables.

1. The markers shall be located above or adjacent to the buried cable:

a) At points of entering and leaving the Public Transport Authority (PTA) property;

b) At changes of direction;

c) At a distance between consecutive markers of the lesser of 200 m or line of sight; and

d) Where specified, at the ends of the under track crossing (the end of the under track crossing is taken as the point 3 m beyond the outer rail or toe of the embankment).


2. The wording on the markers shall include the following:

a) The owner’s name;

b) A warning of the presence of a buried service;

c) The nature of the buried service; and

d) Contact details and advice in the event of an emergency.

3. The markers shall comply with the following requirements:

a) Stand at least 800 mm out of the ground, to the bottom of the marker plate;

b) Be of non-combustible material for the marker plates and of at least fire-resistant material for the pole; and

c) Wording on the markers shall be legible, permanent, and formed in a non-combustible medium, or as otherwise approved by the PTA.

4. The descriptive wording and instructions shown on the markers shall face the railway.

6.1.4 Installation of Power Cables under tracks and elsewhere on railway property

Power cables passing under the tracks shall be enclosed in an appropriate ‘Category A’ system.

The top of the encasing pipe or conduit shall be at a depth of not less than 2000 mm below the top of rail and shall be maintained at this depth for not less 3000 mm beyond the outer rails, when measured at right angles to the track, unless otherwise stated in the approved design.

A ‘Category A’ system is an underground system where:

a) Cables are enclosed in heavy duty insulating conduit without further mechanical protection.

b) Cables are enclosed in insulating wiring enclosures encased in concrete.

c) Sheathed cables are enclosed in galvanised steel pipe without further mechanical protection or

d) Armoured sheathed cables or neutral screened cables are buried direct in the ground without mechanical protection.


Dimension Description Minimum depth (mm)

X Depth between top of rail and conduit, pipe or cable

1200/1500 (directly buried optic)

2000 (power)

Y Depth between top of rail and encasing pipe

1200/2000 (power)

Figure 2 – Section of conduit or pipe-carrying cable under tracks

Power cables passing elsewhere on the property of the PTA shall be laid at a depth of not less than 1000 mm below ground level, or at the same depth below the level of drain inverts they may cross unless, otherwise stated in the approved design.


Where specified by the PTA, the cables shall also be enclosed in conduits or covered by protective slabs.

Figure 3 – Section of cable within and parallel to railway reserve

6.2 Existing Pipes or Cables

Whenever a crossing is made of an existing pipe or cable, such pipe or cable shall be securely supported during the progress of the work.

The minimum spaces required between services are contained in the Utility providers Code of Practice, summarised as follows.


1. Electricity is to pass under gas and water at reticulation crossings.

2. The existing cable shall be protected by a split length of heavy duty conduit or concrete slabs. If 150 mm clearances cannot be maintained then the cable shall be sleeved with a conduit. The length of conduit shall be at least of 500 mm on either side of the crossing.

3. A minimum clearance of 300mm is required between gas and electricity services. If 300mm clearance cannot be achieved, approval of the Gas Service Provider shall be obtained.

4. A minimum clearance of 150mm is required between the electricity services and the sewer and water mains.

5. All reticulation shall be laid within ± 100 mm of the indicated centre line and secured against movement with initial backfill.

6.3 Gas Mains

Where work is required close to the gas transmission system such work shall be performed in accordance with Horizon Power’s Field Instruction – FI 4.1 – Work Adjacent to Gas Mains.

6.4 Communications

The communications alignment is between 500-1300 mm from the property boundary within the verge, and 450 mm deep.

Whenever a cable crosses is a communications cable, the cable shall be securely supported during the process of the work and the power cable shall go under the communications cable, maintaining a 300 mm clearance as per Utility Providers Code of Practice.

The space between the power cable and the communications cables shall be maintained when the trench is backfilled.

Appendix A provides the diagram for the road reserve allocation for utility providers.

6.5 Existing Underground Electrical Cables

Prior to the commencement of excavation work, all efforts must be made to determine if underground cables are present in the vicinity of the proposed excavation. This includes but is not limited to using the “One Call” service.

Work on or near existing underground cables shall be in accordance with Horizon Power’s manual, Working Near Horizon Power’s Overhead and Underground Network and Field Instruction: FI 6.4 Excavation Work and Directional Drilling.

If any unrecorded underground cables, conduits or bare earth wires are exposed, work in the vicinity must cease and Horizon Powers’ CPM must be notified immediately.


6.6 Road and Vehicle Crossings

All cables crossing roads and vehicle crossovers shall be installed in conduits. Road crossings shall be installed:

a) Perpendicular to the property street boundaries; and

b) Between readily recovered target points, e.g., common property boundaries or intersections.

For service cables and streetlight cables, the conduits shall be installed from the edge of the cable alignment to as close as practical to the termination point (e.g. street light column, etc.)

For cables with a large bending radius, road-crossing conduits shall extend a minimum of 1000 mm beyond the kerb into the verge and as practically close to the termination point.

Cable covers shall be installed over cables in the gaps between the end of conduits and the edge of cable alignment, to ensure that the cable is protected until it enters the cable alignment.

Where roads and vehicle crossings are already constructed, thrust boring shall be used to install the required conduits.

Conduit crossing locations shall be permanently identified on the road kerb-face. Typical identification methods could include a:

a) 75 mm high letter “E” embedded or cut in,

b) Proprietary brass plate/letter “E” adhered to the face.

Where conduits are installed across roadways where no kerbs currently exist or will not be installed when the conduits are installed, conduit location as-built drawings shall show the conduit centreline end-point relative to surveyed property boundaries.

6.7 Horizontal Cable Clearance to other Services at Road Crossings

All cables and conduits crossing roads shall be installed with a minimum horizontal clearance of 150 mm from other services.

SECTION 7 Page 7-1


7 CABLE TUNNELS AND SUPPORT SYSTEMS

7.1 General

Where cable tunnels are to be used, the construction and installation requirements shall be included on the design drawings.

Cables running through cable tunnels shall be supported on cleats with a maximum spacing of 1500 mm or on cable ladders.

Horizontal spacing of cable and circuits shall be at least 100 mm between adjacent circuits.

7.2 Access Pits

In circumstances where there is a significant change in direction of the cables being installed, the design may require the installation of an access pit to be large enough to:

a) Allow two people to work comfortably on the cable.

b) install rollers; and

c) Accommodate the bending radii of the largest cable.

7.3 Cable Support

A cleat support system shall be installed in at a distance to ensure the cable is maintained in a straight line and only minimal sagging occurs.

When using cleats, it is necessary to ensure the cable is rigidly held at the cleat position.

Cleats for long vertical runs shall be designed to support the weight of the cable.

Cleats used on single core cable shall be of non-magnetic material, such as wood or aluminium.

Single core cables shall never be surrounded with a steel ring, as this will cause local heating problems.

Care shall be taken to ensure the correct size cleat is used otherwise damage to the cable may result. A tight cleat may pinch the cable whereas a loose cleat may allow excessive cable movement.

Wooden cleats shall be used for paper/lead insulated cables.

SECTION 8 Page 8-2


8 CABLE ON AND OFF “NORMAL” ALIGNMENT

8.1 Standard Cable Alignment

Wherever practicable, cables shall be installed in Horizon Power’s standard alignment of 0 – 500 mm from the property boundary in accordance with the “Utility Providers Code of Practice for Western Australia” and Drawing in Appendix B;

Other services shall not be installed in the power cable alignment without written approval from Horizon Power.

All front boundary pegs shall be identified prior to the commencement of excavation.

8.2 Alternative Cable Alignment

Cables may be installed in the 2.7m alignment where there are installation and maintenance issues adjacent to retaining walls and other structures in the standard 0 – 500 mm alignment.

This is provided it is acceptable to the other Utility Service Providers and it does not interfere with street trees.

In special circumstances if the 2.4 m to 3 m alignment is not available, a written request to the other Utilities’ will be required to obtain approval to use their alignments.

8.3 Easements

Where HV and LV cables are installed outside the standard alignment or in locations other than road reserves, including private property, public open space or public access way, they shall be protected by surveyed and registered easements.

Two types of underground distribution easements exist.

a) Development areas controlled by the West Australian Planning Commission (WAPC) process: Easements are arranged under Section 167 of the Planning and Development Act 2005.

b) Other developments areas: Easements are arranged under the Energy Operators (Power) Act 1979.

The appropriate easement shall be selected and documented in the design file for each particular location.

Note: For subdivision developments, developers shall comply with the requirements of the UDS Manual.

SECTION 8 Page 8-3


8.4 Retrospective Undergrounding

Where the standard cable alignment is not practically available for retrospective underground areas, the cable centre line shall be relocated to a centreline of 2.7 m from the property line (i.e. the standard pole and trees alignment).

The correct property line shall be identified by survey and where there is any doubt as to its correct location, the required directions shall be obtained from the relevant authority.

Where existing overhead electrical apparatus (poles) impedes the installation of underground electrical apparatus (cables) in the 2.7 m alignment, approval may be requested to install the cables on the opposite side of the road in the standard cable alignment.

Where the poles and trees alignment is not available, special arrangements will need to be determined and directed by Horizon Power’s Asset Management support group.

SECTION 9 Page 9-1


9 TRENCHING AND EXCAVATION

9.1 General

All excavation work shall be carried out in accordance with the requirements of:

WorkSafe WA Code of Practice – Excavation

Working near Horizon Powers’ Underground and Overhead Electrical Networks manual

FI 6.4 Excavation Work and Directional Drilling

Trenches shall be excavated to a width sufficient for satisfactory and safe working conditions.

Excavations shall provide the specified minimum cover so as to avoid damage or loss of support to, obstacles such as pipes, drains, cables and other utilities and services.

The excavated area shall be reinstated in accordance with section 16 of this manual.

Note: The use of a dedicated safety observer will be required when excavating with a machine in the vicinity of live or de-energised underground cables or ground mounted electrical apparatus.

9.2 Blasting

On occasions blasting operations may be undertaken for excavation in rock, limestone and clay.

Blasting is not permitted within 30 metres of other utilities and where the blasting will affect their equipment.

Handling and use of explosives for blasting operations shall be carried out by, or under the direct supervision of, a licensed shot-firer.

Adequate warning signs shall be displayed and all precautions against flying material taken by the use of pegged or weighted blasting mats or similar aids

Blasting shall be limited in built up areas and shall only take place when all nearby building occupants have been notified in writing and all buildings have been thoroughly inspected, photographed (where required) and their condition recorded.

Note: Contractors shall pay for any damage or injury caused by blasting.

9.3 Excavated Materials

In built up areas where permitted by the relevant authorities and where practicable, reusable top layers of excavated material such as lawns, pavers, topsoil, etc. shall be

SECTION 10 Page 10-2


neatly stacked on one side of the trench and the bottom layer of soil shall be stacked separately on the opposite side of the trench.

Some Local Government Authorities require all excavated materials, including paving materials to be removed permanently from site to enable continued pedestrian access without having to walk on the road and reduce the potential for vandalism. Unsuitable soil shall be disposed of and graded backfill brought in.

No excavated material shall be placed, or encroach, on private property without the written approval of the owner.

In built up areas, excavated soil shall be covered with tarpaulins or similar protection if weather conditions will cause soil to be washed or blown away.

10 DIRECTIONAL DRILLING

10.1 Installation Principles

Directional drilling is becoming the preferred method of installation for underground works due to improvements in technology and minimum installation disruption.

Conduits and cables shall be installed in accordance with the approved construction drawings.

In general, the following principles shall apply:

a) Each cable shall be installed in a single way conduit.

b) Cable and conduit installations shall be installed between 900 mm minimum depth and 1500 mm maximum depth unless other requirements of this document (e.g. rail crossings) or local site conditions apply.

c) Cable spacing’s shall meet the requirements of Drawing R58 of the Distribution Construction Standards Manual, or as designed for alternative installations.

d) Conduits installed by directional drilling shall not require additional cable protection covers or cable marker tapes.

A maximum of two LV cables of 185 mm², including streetlight cables can be installed in

a common directional drilling bore if there will be no tee or service joints along the

cables.

One 35 mm² HV transformer cable and one LV cable of 185 mm² or less can be installed

in a common directional drilling bore if there will be no tee or service joints along the

LV cable.

Multiple high voltage feeder cables (185 mm², 240 mm² or 400 mm²) shall not be combined into a single directional drilling bore.

Separate directional drilling bores shall be used between 900 mm minimum depth and 1500 mm maximum depth. Cable spacing shall meet the requirements of Drawing R58 of the Distribution Construction Standards Manual.



10.2 Drilling

During construction, continuous monitoring and plotting of the pilot drill and back reamer progress shall be recorded to ensure compliance with the required alignment and installation depth. Refer to Field Instruction Manual FI 6.4 Excavation Work and Directional Drilling. The monitoring may be accomplished either by manual plotting based on the location and depth readings provided by the tracking system or by computer-generated track logs fed by this information. The tracking system shall provide information on:

a) Clock and pitch.

b) Alignment and Depth.

c) Position (x-y).

d) Azimuth - is defined as the direction of cable where a walkover is not possible.

The bore logs shall show a depth and bore position from a known boundary every 3m along the bore line. These records shall be made available to Horizon Power electronically as a permanent record.

To prevent collapse of the borehole, drilling mud or similar material rather than just water shall be used for both drilling and back reaming operations.

Drilling, back-reaming speeds and fluid flow shall be set to ensure spoil is removed without putting unacceptable pressure on the surrounding soil (e.g. surface humping).

During conduit and/or cable installation, pull-back tension shall be set so as to not exceed conduit/cable manufacturers’ maximum pulling tensions.

Note: See Appendix B or Manufacturers’ recommendations for maximum pulling tension for various cable types and sizes.

10.3 Drilling Fluids Management Plan

A drilling fluids management plan shall be completed prior to the commencement of directional drilling work. The plan shall contain the following:

a) Method of slurry containment.

b) Method of recycling drilling fluids and spoil if applicable.

c) Method of transporting drilling fluids and spoil off site.

d) Drilling fluid pressures.

e) Measures to contain and clean the affected area for inadvertent return of drilling or hydraulic fluids.

f) Measures to adequately clean-up of surface seepage of drilling fluids and spoils.



11 PLOUGHING

1.1.11.1 Ploughing

Ploughing technology allows cables to be ploughed into the ground with an envelope of

clean backfill sand. Ploughing equipment has the capability of installing cables in the

following arrangements:

o Three single core cables (not twisted) in flat or trefoil (triangular)

formation. As a minimum, cores must be transposed at every drum

change.

o Triplex (twisted).

The cable configuration must be surrounded with clean sand that is free of rocks and

other hard formations:

o 150 mm underneath the cable

o 50 mm on either side of the cable

o 300 mm above the cable

Lay orange marker tape over the clean sand, as described in the Marking the ploughed

cable route section, below.

Fill the trench and compact to ground level with remaining material (ensure that stones

and rocks have been removed).



Marking the ploughed cable route Permanent above-ground cable markers must be installed along a cable route as described in Table 1 below.

Table 1 – Cable Marking Requirements

Alignment category Description

Marker tape required? (300 mm

above cables)

Above ground cable

markers required?

A Cable within the standard 0-500 mm alignment

Install cable at a depth of 850 mm. Use orange marker tape above cable.

Yes No

B Cable within the 2.4 – 3.0 m alignment

Install cable at a depth of 850 mm. Use orange marker tape above cable.

Yes No

C

Cable outside road reserve (in remote area where there are no other services or infrastructure in the vicinity)

Install cable at a depth of 1200 mm. Use orange marker tape above cables and above ground cable markers.

Yes Yes

When markers are required (per Table 1, above), they must be placed:

on either side of the road at the crossing point

wherever a cable crosses a boundary (e.g. road reserve property boundary, etc)

and as close as possible to the cable installation

For cables in paddocks and open spaces:

place markers so that the impact or damage to agriculture (including livestock) is

kept to a minimum

place markers at the boundaries if a cable has to cross a paddock

Markers should also be placed:

to signify a change in direction of the cable route

so that adjacent markers are visible from each other

at a maximum distance of 150 m apart



12 CABLE LAYING

12.1 Drum Mounting and Inspection

Prior to installation of cables, the following shall be carried out:

12.1.1 Inspection prior to installation:

Following removal of the drum battens or transport protective covering and prior to commencing cable installation, check:

a) each drum for transport damage;

b) integrity of manufacturer’s seals on inner and outer cable ends;

c) condition of armouring, serving and sheath, particularly damage from drum batten nails;

d) Mechanical damage, corrosion and/or leakage of impregnating oil (where applicable).

If the cable is found to be defective, it shall not be installed and arrangements made for it to be returned to the supplier for replacement.

12.1.2 Preparation for installation

Each drum should be mounted on jacks, cable trailer or cable stands so the cable is preferably pulled from the top and always in the direction opposite to that indicated by the arrow on the drum;

Lighter cables may be laid by mounting the cable drum on its side on a truck-mounted turntable and laying the cable directly into the trench;

Prior to removing the cable drum battens, ensure the drum-spindle is level and that the drum turns freely;

If it is necessary to roll a drum into position prior to mounting, ensure the drum is rolled in the direction indicated by the arrow on the drum;

Cable drums should be positioned in line with the direction of cable pull;

As an alternate to a fixed mounting for the cable drum, cables may be rolled directly into a trench from the drum mounted on mobile plant (e.g. excavator) moving along the trench.

WARNING

Sealed cables may contain methane (a flammable gas)

The cable manufacturing process produces methane inside the cable.

Where a cable has fitted with a heat shrink end cap & pressure relief valve before the cable is cut, any pressure build up shall be

bled by inserting a pin into the valve until no further gas is heard to be escaping.

Cable end cap with pressure relief valve



12.2 Protection of Cables during Installation

Cable should be fed from the top of the drum to prevent cable slack.

When pulling from large drums, the cable should be supported between the drum and the trench with a suitable ramp or rollers to prevent stressing the cable;

Cables shall be kept clear of abrasive surfaces by suitable means, e.g. rollers, etc. to prevent any damage to the cable sheath. The cable shall be placed in the trench without sustaining abrasion damage and without allowing rocks or debris to fall into the trench that could also damage the sheath integrity (allowing termite attack);

Precautions should be taken to prevent the drum from over-rotating and allowing cable slack. A suitable braking mechanism should be installed, either in the form of a drum flange drive or an effective friction brake, e.g. plank brake shoe. Where brake shoes are utilised, care shall be taken to ensure no damage occurs to the cable “Z” (inner) end that protrudes through the drum flange;

On long cable runs or where a cable has significant direction changes (both horizontal and/or vertical), rollers shall be used to ensure minimum pulling or bending of radii are maintained to ensure a smooth pull and avoid damage to the cable;

Cables which are pulled into position by a winch, shall use suitable cable stockings and swivels to prevent damage; and

When installing cable by directional drilling, it is essential the cable sheath is not damaged, since damage to the outer jacket may cause sheath faults or compromise the integrity of the cable termite protection.

12.3 Cable Installation methods

There are numerous methods by which the cable can be pulled into the final installed position. Generally, the most economical methods employ power winches.

If considering only those pulling methods using mechanical winches, then there are four distinct methods:

12.3.1 Stocking Pulling

Cable pulling using a steel mesh cable stocking is probably the most common form of installation for cables up to and including 33 kV. The cable stocking is slipped on to the end of the cable and the winch rope attached.

Application of pulling tension locks the stocking onto the cable sheath. Care shall be taken to ensure the manufacturer’s recommended pulling tensions are nor exceeded as cable damage will result.

12.3.2 Installation using Pulling Eyes

The strength of the cable sheath limits the length and size of the cable that can be pulled by stocking pulling. For long and large cross section cables, pulling-eyes can be fixed directly to cable conductors for pulling the cable.



12.3.3 Bond Pulling

When likely pulling tensions may exceed the tension limit of the cable, straight end pulls may have to be replaced by bond pulls. In this method, the cable is lashed to the pulling rope at close intervals (e.g. every half metre for a distance of 20 metres or more) to distribute the strain of the pulling.

Mechanical padding is required to protect the cable sheath from damage at the lashing points.

12.3.4 Armour Pulling

This system uses the armour wires of a cable as the pulling medium. The armour wires, left extended past the end of the cable, are formed into a pulling eye and the winch rope attached to it.

Caution: This method shall not be used for XLPE cables.

12.3.5 Mechanical Assisted Installation

For long or difficult cable installation or large cable sizes, mechanical assistance can be used to insist installation. Typical methods include:

a) One or more cable “caterpillars” installed mid or multi-point along the cable route to provide intermediate cable thrust;

b) Power assisted driven cable drums.

12.4 Cable Pulling Tensions

Cable pulling tensions shall not exceed the manufacturer’s recommendations.

The maximum recommended pulling tensions when using stocking grips to install un-armoured XLPE cables are shown in Appendix B.

The trench or conduit line should be set out so that any necessary deviations from a straight line occur over the largest possible radius. When pulling cable into conduits incorporating bends or pulling rope rollers, lower maximum pulling tensions may be necessary to avoid the wire pulling rope cutting into the side of the conduit.

Any winch used to pull cables shall have either a facility to automatically limit the pulling tension applied to a cable (a tension fuse) or a continuous reading dynamometer incorporated in the pulling arrangement to enable the actual pulling tension to be monitored.

In special circumstances, cable pulling pits may be required at significant changes in cable route direction. Required pits shall be indicated on the design drawing.

On long or complicated cable installations, intermediate cable feeder equipment (or “caterpillars”) may be required to limit pulling tensions.



12.5 Pulling Speed

To avoid damage due to overruns, the cable should be pulled just fast enough to keep the drum rotating smoothly.

Higher speeds are possible when pulling small cables into straight trenches or conduits with good conditions at the feeding and pulling ends;

Drums with long lengths of cable should not be rotated rapidly as overrun can cause cable damage if pulling is slowed or stopped suddenly.

12.6 Cable Bending Radii

The permissible bending radii of all cables are given in Appendix B. No twists, knots or kinks are permitted.

Where a 3x1 core HV cable is to be laid to transformers or switchgear, the three twisted cores can be separated at termination location (e.g. Triplex style) into three individual cores to reduce the minimum bending radius required.

12.7 Maximum Number of Cable Joints

Underground cable joints between terminal points shall be kept to a minimum. For information on the maximum numbers of through joints that may be installed in any section of cable, refer to the Underground Distribution Scheme (UDS) Manual, Section 9.2.8.7.

12.8 Installation of Cables on Poles

Where cables are installed onto termination poles, the cable shall be installed as directly as possible from the cable trench to the pole. No spare loop of cable is required to be installed at the base of the pole, as it is better to joint in a new section of cable if a termination failure occurs. The section of cable off the standard alignment shall be protected by cable slabs and marker tape.

12.9 Bedding and Backfill

To protect the cable sheath, all cables shall be firmly and uniformly bedded on sand free from rocks or other hard formation. The cable shall be surrounded with a thickness of sand prior to backfilling, bottom by 150 mm and two sides by 100 mm, top by 300 mm as shown in drawings R 55, R 56, R 57, R 58, and R 59 of the Distribution Construction Standards Manual. The upper 300 mm of the backfill to final ground level shall also meet the local government authority’s requirements.

12.10 Depth of Cover for Cables

The depth of cover over cables shall not be less than 850 mm. The depth of cover shall be increased as required to ensure that cable joints will have the required depth of cover.

Property

BoundaryProperty

BoundaryProperty

Boundary



12.11 Cable Protection Covers and Marker Tapes

The cable covers shall comply with the requirements of clauses 3.11.3.3 of AS/NZS 3000:2000 and if required, cable covers and PVC marker tape shall be laid at the required levels, as shown in drawing R 51 Distribution Construction Standards (Placement of Duct beneath Road Crossings)

Where more than one cable is installed, the PVC maker tape or cable cover must be wide enough to fully cover the cables, otherwise additional maker tapes and covers shall be installed.

Additional cable protection shall:

1. be placed maximum 75 mm above the wiring system

2. be not less than 150 mm wide

3. overlap the wiring system by at least 40 mm on each side

4. consist of one or a combination of the following:

a) precast concrete slabs with a minimum thickness of 40 mm and a classification of not less than grade 20 degrees in accordance with AS 3600

b) a continuous concrete pour having a thickness of not less than 75 mm

c) fibrous cement slabs having a thickness of not less than 12 mm

d) bricks (slabs) manufactured specifically for the protection of electric cables

e) polymeric cable cover strip (complying with AS 4702)

f) Other materials that offer the same degree of protection as the materials in items (a) to (e) above.

Note: Conduits installed by directional drilling shall not require cable protection covers and marker tapes.

12.12 Sealing of Cables

To ensure water cannot penetrate into the cable conductors or insulation, ends of cables shall be kept sealed. On completion of the cable pulling, any damaged or non-waterproof pulling eyes or sealing end caps should be removed and the cable resealed, unless it is to be terminated immediately.

Where cables have been cut following installation, both the installed and drum ends shall be sealed immediately, except where the cable is to be jointed immediately

13 CONDUITS

13.1 Application

Conduits complying with Australian Standard AS 2053 shall be used to protect cables where they are installed in the following situations:



a) in easements;

b) exit cables from a distribution substation that is set back from road or property boundary;

c) near retaining walls where there is a danger of cable installation damage due to foundation subsidence;

d) crossing roads;

e) crossing water courses and drains;

f) crossing high pressure gas pipelines;

g) crossing under railway lines or restricted access areas such as airports; and

h) Within bridge crossings.

13.2 Requirements for cables installed outside normal alignments

Where cables are installed outside the 0-500 mm standard alignment or the 2400–3000 mm alignment as approved by Horizon Power for street installation, conduits are NOT required. The cables shall be direct buried, laid in accordance with and protected with cable slabs as shown in Drawing in R 51 Placement of Duct beneath Road Crossings in the Distribution Construction Standards Manual.

13.3 Encased Conduits

In some locations PVC conduits may be encased in concrete pipes, steel pipes or concrete encased steel pipes. Unless approved by Horizon Power, cables shall not be installed directly in concrete conduits due to potential damage to sheaths during installation.

13.4 Sealing of Conduits

All conduits, including spare conduits, shall be effectively sealed at the ends and at couplings;

Sealing of conduits is required to prevent the ingress of water and any foreign material that may cause blockage or flooding of cable pits, basement-type substations and switch rooms;

Wherever possible, suitable conduit plugs or covers should be used for sealing of conduits in lieu of taping or other makeshift arrangements.

Conduit joints and couplings shall be installed and sealed in accordance with the manufacturer’s instructions.

13.5 Installation requirements for Conduits

Where conduits are installed in excavations, they shall be installed:

a) with a minimum cover of 850 mm to the top of the conduit;

b) not more than 1100 mm cover as approved by Horizon Power;



c) where all cables in the trench are all installed in conduits, excavated soil may be used for bedding and backfill, provided it is free of organic matter and rocks of 50 mm diameter or larger;

d) normally in flat, horizontal formation for up to four cables, thereafter in tier formation;

e) for road crossings, in accordance with Section 6.6 – Road and Vehicle Crossings;

f) sealed with suitable end caps;

g) with approved ”draw wires” provided in every conduit;

h) When installed prior to the main cable trenching, installed with marker tape 300 mm above the conduit. The marker tape shall be brought out to ground level at each end, with the conduit end position also being marked with a peg.

The most economical method shall be used to install conduits across roads. Subject to cost, boring is preferred for single or double conduit crossings, where conduits of 100 mm size or larger are required.

For locations where more than two conduits are to be installed together, open excavation methods may be used for crossing roads.

13.6 Pulling Cables through Conduits

Care shall be taken to avoid damaging the outer sheath of the cable where it enters and leaves the duct. Single core bundled XLPE high voltage cables are particularly susceptible due to their uneven shape and thin outer sheath.

To prevent future cable failure a suitable lubricant should be used to reduce the friction between the cable and the duct.

A tapered or belled entry shall be used at the entry end of ducts during pulling to prevent damage to cable.

APPENDIX A - Service Alignment, Depth And Colours For Greenfield Site Page 13


14 CABLE JOINTING AND TERMINATIONS

14.1 General

Underground cable jointing is based on the following “Principles of Good Cable Jointing”:

1. Safety shall never be compromised;

2. Jointing pits should be large enough to allow jointers to work freely;

3. Before joining any cable it must be positively identified by approved testing methods and marked at both ends of the cable;

4. Water barrier within the cables to checked prior to joining the cables:

5. The correct kit for joint and cable size shall be selected;

6. Manufacturers’ jointing instructions shall be followed unless practicalities suggest a variation. Where fixture torque are recommended, apply those with torque wrench;

7. Accurate measuring, cutting, stripping and torque settings and workmanship shall be in accordance with the manufacturer’s instructions;

8. Ground covers shall be used to keep tools & equipment and jointing components clean throughout the job –. (Ensure joints don’t get contaminated with surrounding soil, sand, or moisture);

9. Ensuring enough spare cable so that the cable stripping distances are suitable for lay of cable (after cable is manipulated to correct position) to complete the joint(s) in accordance with the manufacturers requirements;

10. All cable ends are to be sealed after cutting. Where they are not sealed they are to be considered suspicious and checked for water ingress prior to use.

11. Housekeeping – keep the work environment clean by placing used packaging in box as work progresses.

14.2 Cable Joint Excavations

There is no standard size for a jointing pit, however joint sizes vary and therefore the size of the pit in which to carry out the jointing will vary.

To facilitate the joining of Cables and to reduce the impacts on the health and safety of the employee/contractor completing the joints, as a minimum, a pit in the trench should be excavated to the following dimensions:

a) 2 meters wide;

b) 2 meters in either direction (4 meters long) of the joint; and

c) At the same depth as the trench.

Depending upon the depth of the trench / lay of cable; an additional step should be to excavate in the pit to either side of the cable joint to allow for ease of access and facilitate the joiner working on the joint. Fig 1 illustrates the concept.



Figure 4 – Cable joint pit dimensions

The sides of the pits should be covered with tarpaulins or similar to prevent soil from being dislodged while working in the pit.

14.3 Jointing

Before joining any cable it must be positively identified by approved testing methods and marked at both ends of the cable.

Water barrier within the cables must be checked prior to joining the cables to ensure no moisture has penetrated into the cable. (Moisture barrier turns green when water is present) If moisture is detected, the cable must be strip the cable back to the point where no moisture is present.

All jointing equipment shall be installed in accordance with the manufacturer’s instructions supplied with the equipment kit to which they relate.

The use by date of the jointing equipment shall be checked prior to use. Where the used by date has expired, the jointing equipment shall be removed from service and returned to the depots store for disposal.

Ensure no conductive material is left on the XLPE cable. If necessary remove any remaining semi-con material with abrasive paper (sandpaper) then clean with a solvent wipe.

Note: Never use a knife to cut the semi-con. This can create a void and could result in the delaminating of the XLPE screen below the ring cut. When stripping the semi-con screen and you score the XLPE insulation, sandpaper the damaged area to smooth out the void/irregularities

The installer identification tags are required on all joints. They shall be marked and fitted adjacent to the joint or termination equipment as per drawing R39 in the Reference section of the Distribution Construction Standards Manual.

All 22KV rated cables requiring transition joints shall use HU28 or HU29 joint assembly as appropriate.



Shear bolts ends shall be filed back to prevent the sharp edges creating a stress point within the cable joint.

14.4 Termite Proofing

Termite proofing shall be installed over all XLPE to XLPE HV straight joints.

The preferred method of termite proofing shall be of the stocking type, which is fitted over the cable prior to joining. Where the stocking type is not available, termite sheeting may be used in conjunction with heat shrink outer seal of the entire termite protection area. Full heat shrink sleeve as provided in kit or zip shrink if jointing area is restricted

On completion of the joint, the termite stocking can be moved over the joint with a minimum cable overlap of 200mm. The ends of the termite stocking shall be sealed with brass roll springs as provided within termite protection kit.

The remaining overlap of termite sheeting over the joint body should be secured evenly in intervals every 150mm to 200mm with the use of 5mm stainless steel cable ties

14.5 Terminations

All Low Voltage terminations shall be completed in accordance with Part 5 - Low Voltage Underground of the Distribution Construction Standards Manual.

Where no termination drawing exists, all equipment shall be installed in accordance with the manufacturer’s instructions supplied with the equipment kit to which they relate.



14.6 Working Ends

If a cable for a future scheme/connection is laid from a universal pillar, kiosk or a low voltage frame unit in an existing scheme, then the remote end of this cable must not be left on a cable drum.

The cable must be made off, insulated to approved methods and placed in a mini pillar with its top painted white.

In areas where it is not possible to install a pillar, then the remote end of this cable must be made off in a joint/shell located in Horizon Power’s cable alignment. When this method is utilised, the location of the joint/shell (e.g. distance from closest property boundary) must be recorded accurately in GIS.

15 TESTING AND COMMISSIONING

Testing and commissioning shall only be carried out by qualified and Horizon Power authorised personnel and in accordance with:

Horizon Power’s Network Testing & Commissioning Standards

VLF Testing of HV Cables manual

Available on Power Link and the Horizon Power external web site, under Network Contractors. The Tester-in-Charge shall be responsible for carrying out tests in accordance with these standards and recording all test results and additional comments where relevant.



16 REINSTATEMENT

16.1 General

The excavated or disturbed land shall be restored to its original condition. Backfilling and reinstatement of road verges and vehicle crossings as necessary shall be completed within three working days from the time the cables are laid and jointed.

Road reserves and all work sites shall be levelled and left clean and tidy. Debris, trees, stumps and excess soil dug from the excavation shall be removed from site when trench backfilling has been finished.

All materials, stakes, plant and equipment used during installation shall be removed and all work sites left in a safe condition.

All material off cuts, waste materials and general rubbish shall be removed from site and disposed of in accordance with the Local Government Authority’s requirements.

The initial backfill over the bedded cables shall be carried out in accordance with Section 12.9 – Bedding and Backfill of this manual.

Trenches shall be backfilled, reinstated and compacted to their original level and/or in accordance with the requirements for footpaths by the Local Government Authority.

16.2 Compaction

Spoil or other approved filling shall be carefully placed in layers into the trench. Stones, rocks and paving material shall be removed from site and not used as backfill.

All backfilling shall be compacted to a minimum 90% of the density as the surrounding soil in accordance with Horizon Powers’ Network Instruction Manual: FI 5.23 Soil Compaction Testing Requirements to prevent future subsidence.

All results shall be compiled on the “Compaction Test Certificate”

16.3 Levelling

Backfilled excavations shall be levelled so as not to constitute a hazard and shall be to the same as the original unexcavated land.



16.4 Restoration of Surface

On completion of any operations affecting pavements or constructed surfaces, except Greenfield subdivision the pavements or constructed surfaces shall be restored in accordance with the Restoration and Reinstatement Specification for Local Governments in Australia Published by the Institute of Public Works Engineering Australia, which is available at Traffic/Road-works/Working on main roads from Main Roads WA’s web site or through the Institute of Public Works Engineering Australia (WA Division) on the IPWEA website.

Restoration of surface includes restoration of all type of footpath materials, e.g. bitumen, brick paving, liquid limestone, etc.

Where cement footpath slabs have been removed to allow cable trench excavation, they shall be replaced and reinstated in accordance with the Local Government Authority’s requirements unless otherwise directed by the Horizon Power.

17 DAMAGE TO PROPERTY

17.1 General

In all areas where cable installation work has been carried out, except as approved by Horizon Power, property or services damaged shall be repaired or replaced as soon as possible after making safe.

Fences around areas holding livestock shall be secured at all times and if damaged during construction shall be repaired or made safe immediately to prevent the stock from straying.

Damage to reticulation systems and underground services that are disturbed or damaged shall be restored to working order.

Trees planted in the road verge shall be protected as far as possible. Tree limbs interfering with the construction shall be removed appropriately by pruning and sealing and the trees left in a reasonable condition.

Inspection shall be done of any structures located along the cable trench route prior to the commencement of works and arrangements shall be made to protect these structures if there is a possibility of damage or hazards occurring.

Horizon Power’s CPM shall be notified in all cases of such damage or hazards occurring.



18 PILLARS AND PITS

18.1 General

Where approved by Horizon Power, service pillars shall be located within the lot boundaries at the corner, adjacent to common boundaries where possible, refer to the Utilities Code of Practice for Western Australia for Road Reserve allocations.

Uni Pillar Mini pillar

Horizon Power Unmetered Pit



APPENDIX A - SERVICE ALIGNMENT, DEPTH AND COLOURS FOR GREENFIELD

SITE

Source: Figure B2 – Utility Provider Code of Practice

Note: The minimum depth of cover required for Horizon Power’s cables is 850 mm.

However, the depth of cover of cables in nominal cable alignment shall be increased as required so that cables joints will have the necessary depth of cover.

Standard Service and Pipe Colours:

Utility Service and Pipe Colours Gas Yellow pipe or Yellow Striped pipe

Electrical Orange pipe or Orange Striped black pipe or Orange

electrical tape for directly buried black sheathed cable

MRWA a) Traffic Signals b) Roadside Lighting c) ITS

a) Orange pipe b) Orange pipe c) Orange pipe (power) and White pipe (communications)

Telecommunications White pipe or black pipe with White Stripe

Water Blue pipe or Blue Striped pipe

Sewerage Cream pipe or Grey pipe or Cream/Grey Striped pipe

“Third Pipe”/Effluent Reuse

Purple pipe

Note: Colours of pipe relate only to PVC and polyethylene pipe and other materials could be used,

particularly in older established areas unless otherwise stated. Some services can be buried

directly in the ground and not in conduits.

WARNING In existing areas, pipes and conduits of other Utilities may not conform to these standards

850mm

APPENDIX B – Cable Installation Data Page 21


APPENDIX B – CABLE INSTALLATION DATA

Typical cable reference data, including data relating to cable installation, is shown below.

APPENDIX C - DIAL BEFORE YOU DIG SERVICE

C1 General

Dial Before You Dig Service (sometimes referred as One Call System) provides a single National point of contact between excavators and utilities that own assets including buried pipes and cables, as well as the owners of other buried services.

This free service makes it safer and easier for people undertaking excavation activities.

C2 Further information

For further information on Dial Before You Dig, telephone (08) 9424 8116 or (08) 9424 8117 during office hours (Perth). Further information on Telstra assets can be obtained directly by telephoning 1800 806 246.

Type of Cable

Volts (kV)

No of Cores

Cable Size

(mm 2)

Cond’r Material

Drum Length

(m)

Nominal Cable core Dia

(mm)

Nominal Overall Cable

Dia (mm)

Maximum Pulling Tension (kN)

Minimum Bending Radii

(Bundle/One Cable)

1 x Sheath stocking

over all cores

3 x Sheath stockings

one on each core

(per core)

Conductor grip

(per core)

Pulling (mm)

Set (mm)

Transformer cable

33 3x1c Triplex

50

Al 250 34.4 80 (3c) 7.5 7.5 2.5 1120/860 740/520

HV Feeder Cable

33 3x1c Triplex

95

Al 250 37.9 94 (3c) 9.8 13.5 4.7 1220/950 820/570

HV Feeder Cable

33 3x1c Triplex

185

Al 250 42.8 97 (3c) 11.1 15.3 9.2 1390/1070 920/640

HV Feeder Cable

33 3x1 630 Cu 500 30.9 65.4(1c) 7.95 1640 980

HV Feeder Cable

33 3x1 1000 Al 500 39.7 72.2(1c) 8.86 1805 1085

Transformer cable

12.7/22 3x1c Triplex

35

Al 250 27 69 (3c) 5.2 5.2 1.75 870/680 580/410

HV Feeder cable


185

Al 250 36.4 87 (3c) 9.4 4.4 9.25 1210/930 810/560

HV Feeder cable


240

Cu 250 38.7 95 (3c) 10 4.6 16.8 1310/1010 870/610

HV Feeder cable


400

Al 250 48.8 105 (3c) 12.6 5.9 20

1480/1140 980/690

LV Feeder cable

0.6/1 1x3c 120+ Wave N

Al 250 NA 38.7 5.2 NA NA 565 375

LV Feeder cable

0.6/1 1x3c 185+ Wave N

Al 250 NA 46 7.7 NA NA 880 590

LV Feeder cable

0.6/1 1x3c 240+ Wave N

Al 250 NA 51 10 NA NA 970 650

Service 0.6/1 1x3c 25+ Wave N

Cu 250 NA 26 2.2 NA NA 220 220

Street Lighting

0.6/1 1 10+ Wave N

Cu 1000 NA 13 1.0 NA NA 100 100

Street Lighting

0.6/1 1 16+ Wave N

Cu 1000 NA 14 1.5 NA NA 120 120

Last review: October 2018 DM# Page | 1 - Horizon Power · for underground cable installation work....

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Transcript of Last review: October 2018 DM# Page | 1 - Horizon Power · for underground cable installation work....