Division Manual: Overhead Design

DIVISION MANUAL: OVERHEAD DESIGN MANUAL Issue No. X

Manual
CEOM7097

For questions regarding or permission to release this

Policy, please contact Essential Energy’s Chief Risk
and Compliance Officer.

If working from a printed copy of this document,

check Policy Alerts and the Policy Library regularly
for updates.

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Approved By: Principal Engineer Overhead
Next review date: August 2023
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CONTENTS
1.0 PURPOSE .....................................................................................................................................4
2.0 SCOPE ..........................................................................................................................................4
3.0 ACTIONS ......................................................................................................................................4
3.1 General......................................................................................................................................4
3.2 Responsibilities ........................................................................................................................5
3.2.1 Variation Approvals .......................................................................................................... 7
3.2.1.1 For Contestable Works.................................................................................................7
3.2.1.2 For Non-Contestable Works: ........................................................................................7
3.2.2 Blasting near Essential Energy assets ............................................................................ 8
3.3 Methods of Supply ...................................................................................................................8
3.3.1 Service from the Existing Low Voltage Reticulation System – Nominally 400/230V .... 8
3.3.2 Direct Distributor – Nominally 400/230V .......................................................................... 8
3.3.3 Customer Substation – Nominally 11000, 22000 or 33000V/400/230V ........................... 9
3.3.4 High Voltage Supply – Nominally 11000, 22000 or 33000V ............................................ 9
3.4 Methods of Construction and Materials..................................................................................9
3.4.1 Materials Used for Construction .................................................................................... 11
3.4.2 Reporting Potentially Dangerous Conditions ............................................................... 11
3.5 Overhead Design and Construction Requirements .............................................................11
3.5.1 Environmental Considerations....................................................................................... 11
3.5.2 Vegetation Management ................................................................................................. 12
3.5.3 Easements ....................................................................................................................... 12
3.5.4 Construction Plans ......................................................................................................... 13
3.5.5 Network Asset Identification .......................................................................................... 14
3.5.6 Overhead Distribution Line Design Parameters............................................................ 14
3.5.6.1 Assessment of Maximum Demand .............................................................................14
3.5.6.2 Maximum Low Voltage Distributor Loading ................................................................14
3.5.6.3 Maximum Voltage Drop ..............................................................................................15
3.5.6.4 Quality of Supply ........................................................................................................15
3.5.6.5 Levels of Reliability ....................................................................................................15
3.5.6.6 Clearances and Spacings ..........................................................................................16
3.5.6.7 Standard Design Temperatures .................................................................................18
3.5.6.8 Wind Return Periods and Design Wind Pressures .....................................................19
3.5.6.9 Line Angles of Deviation and Conductor Uplift............................................................21
3.5.7 Standard Overhead Conductors and Cables................................................................. 21
3.5.7.1 Bare Overhead Line Conductors ................................................................................21
3.5.7.2 Stay Wire ...................................................................................................................22
3.5.7.3 Low Voltage Aerial Bundled Cable (LVABC) ..............................................................23
3.5.7.4 High Voltage Covered Conductor (CCT) ....................................................................23
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3.5.7.5 Conductor Fittings ......................................................................................................23

3.5.8 Standard Stringing for Overhead Conductors .............................................................. 24
3.5.9 Poles ................................................................................................................................ 26
3.5.9.1 Pole Foundations .......................................................................................................26
3.5.9.2 Pole Staying ...............................................................................................................27
3.5.9.3 Use of Temporary Stays .............................................................................................28
3.5.9.4 Pole Placement ..........................................................................................................28
3.5.9.5 Pole Type ...................................................................................................................29
3.5.9.6 Supplementary Fittings to Poles and/or Conductors ...................................................30
3.5.10 Timber pole assessment for additional loads ............................................................... 31
3.5.11 Distribution Substations ................................................................................................. 32
3.5.12 Earthing ........................................................................................................................... 34
3.5.13 Protection of Overhead Networks .................................................................................. 34
3.5.13.1 High Voltage Overhead Networks ..............................................................................34
3.5.13.2 Protection of Low Voltage Overhead Networks ..........................................................35
3.5.14 Insulation Co-ordination ................................................................................................. 37
3.5.15 Special Requirements of Other Authorities................................................................... 38
3.5.15.1 Rail Crossings ............................................................................................................38
3.5.15.2 Crossings of Waterways .............................................................................................39
3.5.15.3 Transgrid Undercrossings ..........................................................................................39
3.5.15.4 Overhead Lines Near Aircraft Landing Fields .............................................................39
3.5.15.5 Co-ordination of Power and Conductive Telecommunication Cables/Systems ...........40
3.5.15.6 Overcrossing or Undercrossing of Essential Energy lines (e.g.: Solar farm, Wind farm
lines) 40
3.6 Load Types and Values..........................................................................................................40
3.7 Load Density Values for Assessment of Maximum Demand ..............................................42
3.8 Conductor Information...........................................................................................................42
4.0 AUTHORITIES AND RESPONSIBILITIES ..................................................................................44
5.0 DEFINITIONS ..............................................................................................................................44
6.0 REFERENCES ............................................................................................................................45
7.0 RECORDKEEPING .....................................................................................................................48
8.0 REVISIONS .................................................................................................................................48

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1.0 PURPOSE

This document outlines the basic requirements for the design of all overhead distribution power lines
within the franchise area covered by Essential Energy so as to ensure a standardised network.

Essential Energy’s objective is to provide a safe, reliable, efficient, and economical electricity distribution
system. To achieve this objective, the overhead network shall be designed in accordance with the
requirements of all Essential Energy policy documents, including this document, and all the design and
construction standards, specifications, Acts and Regulations referenced herein or issued by Essential
Energy.

2.0 SCOPE
These design requirements apply to new works on the distribution network associated with customer
connections (i.e. Contestable Works) and augmentation or refurbishment required by the Network owner.
For information relating to subtransmission line requirements, refer to Essential Energy’s
Subtransmission Design and Construction Standards CEOM7081 and CEOM7082.

The design process may introduce risk to Essential Energy unless the process is controlled, and due
consideration given to Work Health and Safety issues during the design phase. Design control seeks to
eliminate risks emanating from the design process through the implementation of procedures that
identify and account for risk in design activities such as the construction and use of plant, equipment,
facilities, and processes.

The fundamental principles outlined in AS5577 exist for the support of the safety of the public, and
persons near or working on the network; the protection of property and network assets; safety aspects
arising from the protection of the environment, including protection from ignition of fires by electricity
networks; and the safety aspects arising from the loss of electricity supply.

3.0 ACTIONS
3.1 General
Distribution Substations and the electricity reticulation systems in overhead supplied developments must
be installed in accordance with the requirements of this Network Standard and all design and
construction standards and specifications referenced in this document or issued by Essential Energy.

Detailed design of electricity reticulation systems depends on assessed maximum demands, building
and street layouts, street lighting requirements and other local factors. The design information and
parameters specified in this Network Standard provide for minimum acceptable standards. Any
deviations from this specification must be submitted to Essential Energy for approval before they are
implemented as per clause 3.2.1.

Where new developments take place in overhead reticulated areas, Essential Energy will determine the
extent of undergrounding of existing overhead mains that may be necessary. For new subdivisions,
dedicated roadway sites for future substations and cable easements for future use may also be required
by Essential Energy. For underground supply requirements refer to CEOM7098 Underground
Construction: Underground Design Manual.

Street lighting design may form part of the low voltage system design in new developments and must
conform to the requirements of both the street lighting customer and Essential Energy. Approval of the
street lighting customer for the applicable street lighting charges must be obtained first before
construction work commences. Refer also to section CEOM7107 Distribution Overhead Mains – Lighting
of the Overhead Construction Manual CEOM7099.

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This document should be read in conjunction with the Electrical Standards and Network Standards listed
in Section 4 – References.

3.2 Responsibilities

During the course of supply negotiations, the Accredited Service Provider (ASP) shall provide all
information to allow Essential Energy to determine the most appropriate method of supply (as described
in Clause 3.3). Refer to Contestable Work: Design Information Application CEOF6010. All applications
for a new connection or connection alteration also require an online application to be submitted through
Essential Energy’s connection portal on Essential Energy’s website. A connection application is not
required for subdivisions.

Accredited Designers (Level 3 ASPs) should be aware of and advise on the possibility of any demand
management opportunities and options that may be available when considering new or additional load
application.

Essential Energy’s Contestable Design and Certification Team (Network Design Group) will prepare and
provide design information sufficient to enable design and construction drawings to be completed.

Overhead designs must be prepared by an Accredited Designer. The Level 3 ASP is responsible for the
design and Level 1 ASP is responsible for supply of some materials and construction of the electricity
reticulation system (including substations) to supply the new development as detailed in Essential
Energy’s design information. The relevant ASP is also responsible for providing local authorities and the
NSW Roads and Maritime Services (as appropriate) with copies of the proposed construction plans at
least 40 days before work is to commence and must comply with any special requirements of these
authorities. These special requirements, along with any services that are in close proximity of the new
development, must be indicated on the construction plan. In addition, where other authorities such as the
State Rail Authority or Waterways Authority have jurisdiction over land or water impacted by
development, special additional conditions may apply. As these may vary from time to time, current
applicable conditions must be checked at the time of the development/construction.

Prior to commencing excavation works, a Dial Before You Dig search must be completed.

Level 3 ASPs are to conduct a Dial Before You Dig (DBYD) search for all projects they design. All
relevant information shall be included on the design construction drawings along with the DBYD Job
Number and Expiry Date, in accordance with CEOM7001 Network Services: Design Construction
Drawings. Level 3 ASPs shall ensure their design does not impact upon existing underground services.

The relevant ASP should always be mindful of the need for safe work practices and the minimisation of
operational interference between power systems and cabled telecommunication systems.

Essential Energy poles may have third party attachments installed that are not owned by Essential
Energy. It is the applicant’s responsibility to verify whether there are any third-party attachments installed
and to organise with the attachment owner a suitable time to facilitate the relocation of their attachment
using the form CEOF6586. The attachment owner may charge a fee to conduct the relocation works.

The relevant ASP is also required to carry out an environmental review at the design stage of the project
in accordance with the Environmental Planning and Assessment Act 1979 (EP & A Act). It is a
requirement that the ASP considers all Environmental Planning Instruments (EPIs). Applicable EPIs in
most cases will include Local Environment Plans (LEPs), Regional Environmental Plans (REPs) and
State Environmental Planning Policies (SEPPs). An Environmental Impact Assessment (EIA), including
bushfire protection measures as outlined in the Planning for Bushfire Protection 2001 guidelines, must
consider not only the construction itself but also the ongoing operation and maintenance of the assets.

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Where easements are required, it will be the responsibility of the Accredited Designer (Level 3 ASP) to
arrange for such easements in favour of Essential Energy and in accordance with the relevant
information contained in this or other documents issued by Essential Energy. Refer to CEOP8046
Network Planning: Easement Requirements, and the Design Information Package for the project.

Level 3 ASPs are responsible for arranging the surveying and pegging of proposed asset locations to
allow plant and equipment to be installed as designed and to simplify auditing on completion of the
installation.

Level 1 ASPs and/or Level 2 ASPs are responsible for arranging surveying and pegging of property
boundary locations and final ground levels as well as all other non-electrical work such as tree clearing,
excavation, restoration, landscaping, and any construction that supports the proposed electrical work.

It is important to note that it is the responsibility of an ASP to report any Network component associated
with or being considered in a project that may be in an unsafe or dangerous condition to Essential
Energy’s Network Construction Inspector or local Area Manager/Resource Supervisor for assessment
and remedial action.

Non-electrical and civil works close to Essential Energy’s electrical network must be undertaken in
accordance with Essential Energy’s Electrical Safety Rules subject to specific accreditation
requirements. In addition to this requirement, the SafeWork NSW Code of Practice: Work Near
Overhead Powerlines and the Essential Energy Operational Procedure: Work Near Essential Energy's
Underground Assets CEOP8041 should be reviewed prior to undertaking any works.

Risk assessment needs to be conducted on all designs including excavation close to network assets.
With regards to risk assessment, particular attention needs to be given to Work Health and Safety Act
2011 (NSW) (WHS Act), Work Health and Safety Regulation 2017 (NSW) (WHS Regulation) and
AS/NZS3012 – Electrical installations — Construction and demolition sites.

In accordance with AS5577 Electrical Network Safety Management Systems, hazards associated with
the design, construction, commissioning, operation, maintenance, and decommissioning of electrical
networks are to be identified, recorded, assessed, and managed by eliminating safety risks so far as is
reasonably practicable, and if it is not reasonably practicable to do so, by reducing those risks to as low
as reasonably practicable.

The Level 3 ASP/designer must provide a written Designer Safety Report for the designs they provide in
accordance with the WHS Act and WHS Regulation. The Safe Design of Structures Code of Practice
July 2012 is a practical guide to achieving the standards of health, safety and welfare required under the
WHS Act and the WHS Regulations. A site visit should be conducted in preparing the Designer Safety
Report. The Designer Safety Report shall be attached to the construction plan. The Level 3 ASP may
choose a suitable company format for presentation of the Designer Safety Report in accordance with the
WHS Act and WHS Regulation.

As part of the Designer Safety Report the designer must provide a design report listing the design
clearances after assessing the required height of each new span. This design report shall consider land
use and local risk factors to determine if higher clearances than the values listed in Table 3.5.6.6.1 may
be required. The design clearances for each span shall be listed in a table on the construction drawings
or contained in the design report submitted as part of the Designer Safety Report including reasons for
additional clearances in excess of Table 3.5.6.6.1. The information should also clearly identify the point
in the span with the minimum design clearance and lateral distance to the adjacent pole. Consideration
shall be given to not installing power lines in locations including but not limited to between two silos, over
stock loading facilities, over playgrounds, near airports or pools etc.

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All design work must be undertaken in accordance with all relevant legislation and regulatory
requirements. In the event of any inconsistency between Essential Energy’s Design and Construction
Standards and Work Health and Safety requirements, designers’ Work Health and Safety obligations will
take precedence. However, where an inconsistency is identified the designer must obtain authorisation
from Essential Energy before incorporating a variation to an Essential Energy Standard in a design.
Refer to Clause 3.2.1 Variation Approvals.

Essential Energy takes no responsibility for non-electrical and civil works carried out by external parties
such as ASPs, civil contractors etc. At all times, these parties are responsible for the safety and
maintenance of such works close to overhead and underground network assets in accordance with
Essential Energy's standards and specifications notwithstanding that Essential Energy may be
undertaking work on or adjacent to these assets. All relevant legislation and regulations in relation to
such works must be complied with including any environmental legislation or regulations. Essential
Energy shall be consulted before commencement of such works with appropriate notice so that if
required Essential Energy can visit the site or provide timely advice, as these works may affect the
integrity of assets (for example: pole footings, earthing systems, underground cable systems).

The customer (end user) is responsible for supplying and installing service mains from the Point of
Common Coupling to the Connection Point in accordance with the Service and Installation Rules of New
South Wales and CEOM7097. Where the requirements in these documents differ, the CEOM7097
requirements shall take precedence.

3.2.1 Variation Approvals

At the time of a request for the approval of a non-standard design/works, appropriate documentation
shall be provided to Essential Energy as per clause 3.2.

3.2.1.1 For Contestable Works

The Level 2 ASP shall gain approval in writing by Essential Energy’s ASP Relationship Team for any
variations from the standard design requirements. Contact ASPinfo@essentialenergy.com.au. This
approval shall be obtained prior to proceeding with contestable work.

The Level 3 ASP shall gain approval in writing by Essential Energy’s Contestable Design and
Certification Team (Network Design Group) for any variations from the standard design requirements.
This approval shall be obtained prior to proceeding with contestable work.

Level 1 ASP’s shall ensure that the appropriate approvals have been obtained by the level 3 ASP prior to
constructing a non-standard construction. If it is identified that a standard is required to be varied at the
time of construction, the Level 3 ASP shall assess the changes and obtain the appropriate approvals
prior to construction.

3.2.1.2 For Non-Contestable Works:

The designer shall gain approval by Essential Energy’s Network Design Engineering Manager for any
variations from the standard design requirements. This approval shall be obtained prior to proceeding
with work.

The constructor shall ensure that the appropriate approvals have been obtained by the designer, prior to
constructing a non-standard construction.

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3.2.2 Blasting near Essential Energy assets

Essential Energy accepts a level of 25mm/s peak component particle velocity upper limit as per
AS2187.2 Appendix J for blasting operations in the vicinity of powerlines. In addition to the management
of ground vibration, control of fly rock shall be implemented. Components such as insulators and
conductors are particularly susceptible to damage from fly rock and adequate control measures including
the use of blast mats or equivalent should be used to manage this. Air blast limit shall be 133 dBL as per
AS2187.2 Appendix J.

The blasting contractor shall contact Essential Energy's Network Assurance Team in each instance
where blasting is required. In some circumstances, Essential Energy may require that certain parts of the
network are de-energised while blasting is carried out or modifications to support the network during
blasting activities are carried out. In these circumstances, the contractor must request an outage as per
Essential Energy’s policies nominated by System Control Group and/or comply with the requirements for
modification of the network. Essential Energy may also specify other parties that need to be contacted
prior to commencing any blasting operations such as critical electricity customers in the vicinity and
Essential Energy Regional Management.

3.3 Methods of Supply

There are four approved methods of supply. The appropriate choice to be utilised is dependent on the
assessed and foreseeable maximum demand of the development. For guidance on connections for High
Voltage Customers and Embedded Generators refer to CEOP8079 Connection Process: For Negotiated
High Voltage Retail Customer Connection and Embedded Generators >30kW.

The decision as to the most appropriate method of supply will be made by Essential Energy as part of
the supply negotiation phase. This initial step in the process of establishing an electricity supply involves
exchange of details pertaining to the development between the developer, customer, and Essential
Energy. The options for electricity supply are listed in clauses 3.3.1 to 3.3.4.

3.3.1 Service from the Existing Low Voltage Reticulation System – Nominally 400/230V

This may provide for the connection of services (overhead or underground) rated up to 400 amps.
Overhead services should be restricted to a rating of 275A or 4-core 150mm2 LVABC. For higher rating
up to 400A, 4 Core 95mm2 run in parallel may be considered subject to approval from Essential Energy.
Refer to Clause 3.2.1

This method of supply is limited by the available capacity of the existing reticulation system and the
associated distribution substations.

Reference should be made to the Service and Installation Rules of New South Wales, and to clause
3.3.2 of this document for rural area requirements.

3.3.2 Direct Distributor – Nominally 400/230V

Overhead mains taken from a distribution substation remote from the customer’s premises which can,
subject to certain constraints, supply up to 400 amps. This method of supply is restricted by voltage drop
and the capacity of the distribution substation, as well as fluctuation, distortion, and interference
considerations, as defined in Service and Installation Rules of New South Wales.

Essential Energy operates a predominantly rural network generally considered to be bushfire prone
environments with different degrees of risk to the public from low to high.

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For rural areas, all new low voltage connections and service mains, and upgrades to existing overhead
service mains due to capacity increases must be underground even if the service mains are to be
connected to an overhead distribution line. Line routes should be selected to negate the need for road
crossing (service) poles. Consideration should be given to excavation around SWER substation poles as
excavation in the vicinity could damage the SWER earthing system. Variations from this requirement
may be permitted in exceptional circumstances only after approval from Essential Energy. Refer to
Clause 3.2.1. These circumstances may include but are not limited to situations where under grounding
is not economically viable due to the type of terrain (e.g. rock terrain, waterway crossing or underboring
of a public road). Where approval is obtained for overhead construction, LVABC is the standard
insulated overhead cable to be used.

3.3.3 Customer Substation – Nominally 11000, 22000 or 33000V/400/230V

Essential Energy may determine that the existing LV network is unable to meet the customers supply
requirements. In such cases, the customer shall be required to provide a suitable space and approved
easement or lease to accommodate Essential Energy’s transformer(s), pole, switchgear, and other
associated equipment. Generally, supply by this method will be restricted to the capacity of a 500kVA
pole-mounted substation or a 1500kVA padmounted substation rated appropriately for the load cycle
imposed by the customer, however, larger installation may be possible. Reference is made to
'Accommodation of Electricity Distributor's Substation Equipment' section in the Service and Installation
Rules of New South Wales. For contestable works, the Level 3 ASP must discuss arrangements for
electricity supply with Essential Energy’s designated Design Certification Officer prior to finalising their
preliminary development design. For non-contestable works, approval is required from the local Planning
team.

A list of all distribution pole-mounted substation types and their approximate ratings is provided in Clause
3.5.11.

Where supply is taken direct from a customer’s substation, the customer’s main switchboard shall,
wherever practicable, be located immediately adjacent to the substation. If the customer’s main
switchboard cannot be located immediately adjacent to the substation, the proposed location must be
approved by Essential Energy before the design proceeds. For contestable works, approval is by the
Design Certification Officer. For non-contestable works, approval is required from the local Planning
team.

3.3.4 High Voltage Supply – Nominally 11000, 22000 or 33000V

Consideration will be given to application for high voltage supply in accordance with the requirements of
the Service and Installation Rules of New South Wales where, in the opinion of Essential Energy, it
satisfies technical or economic considerations and the customer is able to safely operate and maintain
the high voltage network. This option is not available in some areas and is restricted to premises with
single customers. Where this option is considered a possibility, Essential Energy will provide the design
information to the developer as required on a project-specific basis.

3.4 Methods of Construction and Materials

Essential Energy’s Asset Management and Engineering Group is the determining authority as to the
form of construction to be used for individual projects, including contestable works. Essential Energy’s
networks have been categorised as urban and rural. Rural networks are as defined as that part of a
network:
a. where the average demand on the high voltage feeders within it is less than 0.3 MVA/km, or
b. that is in an area zoned as rural under a local environment plan (made under the Environmental
Planning and Assessment Act 1979 (NSW) or
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c. that is in an area that is predominantly used for agricultural purposes.

And may include isolated industrial/commercial developments.

Urban network is defined as that part of a network that is not a rural network.

In urban areas where overhead construction is specified for high voltage reticulation the small delta
construction shall be used and for low voltage reticulation, low voltage aerial bundled cables shall be
used as the standard construction. In rural areas Essential Energy shall stipulate the type of construction
to be used and material types as may be appropriate in identified bushfire-prone areas.

Where overhead construction is specified for high voltage reticulation (e.g. rural networks) the
construction shall be either of the open wire construction type or covered conductor type. Essential
Energy shall be the determining authority as to which type is the most appropriate and may also stipulate
material types to be used in identified bushfire-prone areas.

For bare conductors, as per AS/NZS 7000 section 3.7.3 note 5, a k factor of 0.6 must be used in designs
for P1 bushfire risk areas. Bushfire risk areas will be noted in the design information package for the
project.

In general, it is expected that high voltage lines in rural areas shall utilise the standard delta
configuration.

Pole top constructions for substations in rural areas shall use the small delta construction subject to the
following:

• The small delta is the preferred construction in these situations and the crossarm length should be
increased in the first instance if required for mid span separations. If maximum crossarm length
does not deliver sufficient mid span separation, then use of standard delta over small delta may be
considered as follows:

• When adding a single-phase substation to existing poles that have a standard delta construction,
connection of the transformer on the lower phase conductors may be acceptable subject to
satisfactory load balancing of the feeder.
• When adding a three-phase substation to existing poles that have a standard delta construction,
the construction shall be upgraded, or a design assessment is required to retain the standard delta.

Where an ASP has reason to prepare a design that varies with the requirements stipulated in the
Essential Energy Construction Manual, the designer must first gain approval from Essential Energy.
Refer to Clause 3.2.1.

The final interpretation and decision as to the type of construction to be used shall be as stated in
Essential Energy’s design information package issued for the project.

The general guidelines for the form of construction for each project shall be determined by Essential
Energy’s local Planning team and shall be in accordance with the prevailing policy of the time.

Flat constructions should not be used for high voltage lines except in a dual circuit mid-pole situation.

The use of high voltage raiser brackets to retrofit existing low voltage overhead lines is NOT a standard
construction.

The enclosed switch is the standard switch to be used on the Essential Energy distribution network.
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Enclosed switches with galvanised fittings shall NOT be used in coastal locations. Enclosed switches
with stainless steel fittings are to be used. For the purposes of this clause, coastal locations include the
following townships, and their adjacent local towns and villages: Ballina, Batemans Bay, Bulahdelah,
Byron Bay, Coffs Harbour, Eden, Ewingsdale, Forster, Gloucester, Grafton, Kempsey, Maclean,
Macksville, Merimbula, Murwillumbah, Nambucca Heads, Narooma, Port Macquarie, Taree, Tweed
Heads, Woodburn, Bega, and Moruya.

Extension of the low voltage mains could be overhead reticulation or underground depending on the
situation and as determined during the design information process.

3.4.1 Materials Used for Construction

Selection of materials to be used for all new construction works are to come from Essential Energy’s
policy CEOM7004 Materials Inventory: Contestability (Approved).

The design shall be assessed for compliance with this standard on the basis that the bill of materials for
the project must be items contained within the Approved Materials List.

A complete bill of materials for the project must be forwarded to Essential Energy prior to
commencement. This must indicate quantities, where all materials have been sourced and all necessary
documentation from the supplier must accompany the bill of materials. Where overhead conductors are
used, the manufacturer’s name and conductor drum number shall be recorded. This allows Essential
Energy to identify the location of the materials used if there is a problem with an item at a later date.

3.4.2 Reporting Potentially Dangerous Conditions

If the Level 3 ASP (Accredited Designer), during the design stage, or the Level 1 or 2 ASP, during the
pre-job hazard assessment check or during the progress of work, believes that a pole or other network
component may be in an unsafe or dangerous condition, such pole or other network component must be
reported immediately to Essential Energy’s Network Construction Inspector or local Area
Manager/Resource Supervisor for assessment and remedial action.

3.5 Overhead Design and Construction Requirements

Overhead power lines within Essential Energy’s franchise area should be designed and constructed in
accordance with:

• This document
• Standards Australia Limited publication AS/NZS7000 Overhead line design – Detailed procedures
• CEOM7099 Overhead Construction Manual
• CECM1000 Health Safety and Environmental Manual: Index.
• Work Health and Safety Act 2011, Work Health and Safety Regulation 2011 and Safe Design of
Structures Code of Practice July 2012.

The following sections include general issues as a guide for designers.

3.5.1 Environmental Considerations

Designers need to be aware of environmental implications of route selection, materials, and equipment
etc.

It is a requirement that all proposed work must have an appropriate Review of Environmental Factors
(REF) carried out by a person qualified and competent in Essential Energy’s environmental procedures.

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The REF must be carried out in accordance with the Environmental Planning and Assessment Act 1979
(EPA Act) and also in accordance with Essential Energy’s documents CECM1000.70 HSE Manual:
Environmental Impact Assessment NSW, CECM1000.71 HSE Manual: Environmental Impact
Assessment QLD (if appropriate) and CECM1000.90 HSE Manual: Handbook.

For Part 5 assessments under the EPA Act the designer must use Essential Energy documents
CEOF1070.01 Environmental Impact Assessment: Screening Worksheet, CEOF1070.02 Review of
Environmental Factors Worksheet and CEOF1070.03 Consultant checklist: Preparation of Review of
Environmental Factors (REF).

3.5.2 Vegetation Management

Reference is made to CEOP8008 Vegetation Management Plan.

The clearing of vegetation to enable the construction of a new power line should be carried out in
accordance with CEOP2010 Vegetation Clearing Guidelines for New Power Lines.

Should it be necessary for vegetation to be removed near existing overhead power lines then this work
should be carried out in accordance with CEOP2021 Vegetation: Removing Vegetation near Overhead
Powerlines.

3.5.3 Easements

Where an overhead power line, (either existing or new), other than a dedicated connection asset on the
connecting customer’s property, are not or cannot be constructed within a public road reserve, then an
easement will generally be required. Such easements shall be provided in favour of Essential Energy.

Easement widths required will generally be in accordance with the Industry Guidelines (ISSC20) and are
reproduced in CEOP8046 Network Planning: Easement Requirements.

Where easements are required in association with new customer connections that are funded by the
customer, all costs associated with obtaining these easements shall be borne by the customer, some of
those costs being:

• Survey costs.
• Consultation costs (e.g. Crown Land).
• Land valuation expenses.
• Compensation payments.
• Legal expenses, etc.

Where easements are required in association with Network-funded projects (e.g. augmentation of shared
assets) the costs associated with obtaining those easements shall be borne by the Network owner.

Where projects involve both shared and dedicated assets, the costs shall be apportioned between the
customer and Essential Energy Networks, based on:

• New versus existing assets.

• Works initiated by ‘the proponent’.

Reference is made to CEOP8046 Network Planning: Easement Requirements for additional information.

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3.5.4 Construction Plans

A primary function of the design process is to produce a construction plan for use by the customer to
engage an ASP or contractor to construct those assets.

Once constructed, Network assets are generally transferred to the Networks owner and need to be
added to various asset databases, maps, plans, GIS etc.

For these reasons, it is essential that certain minimum information is included on the construction plans
with a reasonable level of standard symbology to allow:

• An ASP to construct those assets.

• Network personnel to update their asset records system.

All design and construction plans shall use the standard symbols and be in the format nominated in
CEOM7001 Network Services: Design Construction Drawings. All network project design and
construction plans are to be identified with a unique project number. Reference is made to previous
Clause 3.2 as to the responsibilities of an ASP in the provision of the necessary information on the
construction plan as well as providing information to the appropriate authorities.

On completion of the construction of a new line, the following ‘as built’ information is to be
recorded/updated on the construction plan:

• As constructed line/pole schedule.

• Final as constructed route plan.

• Final height of the lowest conductor above ground at the nominated design temperature for ground
clearance assessment (Design Temperature for Additional Safety Margin) as per Table 3.5.6.7
along the route of the line.

• Conductor stringing tensions and tables.

• Final earthing value achieved and the earthing configuration for each installation.

Alternatively, a separate design information sheet, or a copy of the design information as provided from
an approved software package displaying the same unique project number as the project drawing, can
be provided. This design information should include conductor stringing details such as the design
tension, initial sags, the final sags, and the minimum ground clearance at the nominated design
temperature for ground clearance assessment (Design Temperature for Additional Safety Margin) as per
Table 3.5.6.7. Also required is the conductor final tension at 5°C with no wind in addition to the conductor
tension under the wind/ice loading condition if applicable to the installation location:

• Line profile for rural extensions, where terrain profile varies by >5% at any point in a span and the
ruling span exceeds 100 metres, or terrain profile is >10% in addition to the provision of property
schedules. Alternatively, a designer may opt to retain a separate profile that can be produced if
and as required by Essential Energy for audit purposes. Recommended scale for route profiles are
1:2500 horizontal and 1:250 vertical.
• Pole foundation details if they vary from the minimum prescribed in Clause 3.5.9.1 of this
document.
• Other assets attached to Essential Energy’s poles.

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3.5.5 Network Asset Identification

Any asset added to Essential Energy’s electrical network must be labelled in accordance with
CEOP8042 Networks: Asset Identification and Operational Labels.

3.5.6 Overhead Distribution Line Design Parameters

Reference is made to the publication by Standards Australia Limited/ Standards New Zealand
Publication AS/NZS7000, being the basis for all Overhead Line Design, and Essential Energy’s
Overhead Construction Manual CEOM7099.

The following additional information is provided to assist in the design process:

3.5.6.1 Assessment of Maximum Demand

The demand for an individual development shall be assessed in accordance with Australian Standard
Publication AS/NZS3000, based on appropriate diversity factors being applied to a submitted list of
maximum demands for all items of equipment. These factors should be used in conjunction with
discussions with the ASP to ensure there are no mitigating circumstances that would negate or reduce
their use.

Where either actual surveyed load data for upgrade work or assessed maximum demands are not
provided for new designs, then recommended After Diversity Maximum Demands (ADMD’s) may be
used. Recommended ADMDs in accordance with the requirements of CEOP8003 Subtransmission and
Distribution Network Planning Criteria and Guidelines are provided in section 3.6.

Where the ADMD in conjunction with the utilisation factor as provided in section 3.6 is used to assess
the transformer capacity required for a project, then a common sense/realistic approach should be
adopted.

There will be occasions, mainly in rural situations, where it may be necessary to differentiate between
the various listed ADMDs to suit a particular project. One project may, due to the type of housing, be
assessed at 7.0kVA/dwelling whereas another project may be assessed at 4.0kVA/dwelling for sizing
transformers.

In the case of industrial, commercial and multi occupant developments, if a full list of connected loads is
not initially available, Essential Energy will nominate a load density value in VA per square metre for floor
area used as provided in section 3.7.

It is also essential that the assessed maximum demand appropriately incorporates any definitive plans
that the customer has for expanding or augmenting the development in the foreseeable future.

3.5.6.2 Maximum Low Voltage Distributor Loading

The following design criteria for the initial electrical loading on low voltage distributors must be satisfied:

• The designed maximum load on any LV distributor must not exceed 75% of the distributor’s
nominal rating, unless otherwise nominated by Essential Energy. This provides a reasonable
margin for load growth and paralleling requirements. Distributors are nominally rated in accordance
with the ambient temperature, the temperature rating of the style of construction and type of
conductor and associated cross-sectional area of materials used.
• The load to be connected to a distribution centre must be balanced across the LV distributors and
their respective phases, unless agreed otherwise.

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3.5.6.3 Maximum Voltage Drop

The ultimate voltage level to be maintained at the Connection Point should be not less than 226 Volts
and not greater than 253 Volts, in accordance with Service and Installation Rules of NSW and
CEOP8026 Electricity Supply Standard.

The designed maximum voltage drop, as determined by ‘LVDROP’ in a low voltage distributor (not
including the service mains) must not exceed 9V at the extremities. ‘LVDROP’ is a design package used
by Essential Energy to assess the effect of new developments connecting to its LV network and is based
on established engineering principles as outline in Section 4 of publication AS/NZS3008.1.1.

The maximum volt drop for the distributor must be calculated and supplied with the design details.

Voltage drops shall be determined using ‘LVDROP’ software (Version 5.48 or later) and the load
information, provided in section 3.6 & 3.7 and conductor impedance values as provided in section 3.8.
Voltage drops submitted with the design will be checked by Essential Energy using the same
methodology and information.

All domestic overhead supply connections are assumed to be single phase unless written undertaking is
provided that the connections will be two or three phase connections.

In general, voltage drop models for single phase loads on a three phase LV system shall be produced by
modelling the heaviest loaded phase. The designer must also consider situations where the remote end
of the distributor has connections which are not on the heaviest loaded phase. The intention is to identify
the worst case design voltage drop on each distributor.

Where three phase segments of the network are to supply one or two customers, then they shall be
modelled in LVDROP as per the following:

• One single phase connection: Enter one load per phase and double the distance of the segment
to account for voltage drop in the neutral.
• Two single phase connections: Enter one load per phase and multiply the distance of the
segment by 1.5 to account for voltage drop in the neutral.

3.5.6.4 Quality of Supply

The designer shall ensure that his design is satisfactory to supply customer equipment that has the
potential to cause interference to other customers. Arc furnaces, welding machines, X-Ray units and
frequently started large motors are examples of equipment that can cause excessive fluctuation of
voltage. The design shall comply with the limits specified in the Service and Installation Rules of New
South Wales, Section 1.10 and meet the requirements of the series of AS61000 for all aspects of
electromagnetic compatibility, particularly for voltage flicker and voltage fluctuation.

3.5.6.5 Levels of Reliability

Low Voltage in Urban and developed areas.

Alternate supply to LV distributors must be provided from adjacent distribution centres wherever
practicable. Each distributor will normally require two alternate points of supply to allow low voltage
paralleling under maximum demand conditions.

Every opportunity must be taken to establish loop feeds where loop roadways exist (i.e. interconnection
between distributors from the same distribution centre or between different branches of the same

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distributor). Extension of distributors beyond that necessary to provide a paralleling path will not normally
be required unless nominated otherwise by Essential Energy’s local Planning team.

In some circumstances a new substation will be required to satisfy the design requirements of Section
3.5.6. Where the new substation is to be installed at a pole with existing low voltage mains, then open
points shall be established in the low voltage mains adjacent to the substation. In determining locations
for LV open points, Essential Energy’s Planning may be consulted to confirm suitable assets on which
low voltage open points will be installed. Low voltage open points will not be permitted on the same pole
as the new substation.

Low voltage links will be required at the low voltage open points in most circumstances.

High Voltage
During the course of supply negotiations Essential Energy’s local Planning team will determine the
minimum level of high voltage reliability required and this information will be provided as part of its
design information. In doing so, Essential Energy will take into account the level of reliability of the
existing network, type of existing construction (i.e. overhead or underground), permissible number of
‘Tee off connections’ allowed, permissible number of substations on a radial supply (both on a temporary
and permanent basis), future load growth and any other network requirements. All costs associated with
levels of reliability in excess Essential Energy requirements shall be met by the customer.

Low Voltage Services

The installation and connection of all service mains shall only be carried out by suitably accredited and
authorised Level 2 ASPs in accordance with the Service and Installation Rules of New South Wales and
CEOM7097. Where the requirements in these documents differ, the CEOM7097 requirements shall take
precedence.

In urban areas, under no conditions are new service mains to be erected so as to cross over the
boundary of any property other than that property for which the service is intended.

Standard overhead services acceptable for connection to Essential Energy’s LV network are those
provided in Table 3.5.7.3.

3.5.6.6 Clearances and Spacings

All new overhead lines that are to be erected and connected to Essential Energy’s network shall have as
a minimum requirement the clearances and spacing’s provided in publication AS/NZS7000, Essential
Energy’s Overhead Construction Manual documents CEOM7106.25, CEOM7106.26, CEOM7106.27 and
Table 3.5.6.6.1 of this document.

Where the clearances stipulated in the following Table 3.5.6.6.1 and those stipulated in documents
CEOM7106.25, CEOM7106.26 and CEOM7106.27 exceed those provided in publication AS/NZS7000
the values stipulated by Essential Energy shall take precedence.

Clearances in CEOM7097 are higher than the minimum clearances listed in AS/NZS 7000 by the
following values:

• Bare or insulated low voltage - 0.5m for all conditions.

• 11, 22 and 33kV - 0.6m over the carriageway of roads. 0.5m over land other than the carriageway
of roads and over land not traversable by vehicles.
• 66 and 132kV - 1.3m over the carriageway of roads. 0.6m over land other than the carriageway of
roads. 0.5m over land not traversable by vehicles.
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The additional clearance stipulated in CEOM7097 over and above that required by AS/NZS7000 is to
ensure minimum clearances required in AS/NZS7000 are achieved in case of site, environmental and
construction variations.

The maximum conductor operating temperatures that apply to the design clearances shown in Table
3.5.6.6.1 are provided in Clause 3.5.6.7.

Distance to Ground in Any Direction (m)

Over Land Which
Over Land Other Due to its
Nominal System Voltage Over the
than the Steepness or
Carriageway
Carriageway of Swampiness is not
of Roads
Roads Traversable by
Vehicles
Bare low voltage
6.0 6.0 5.0
(400/230 Volt) Mains
Insulated low voltage
6.0 6.0 5.0
(400/230 Volt) Mains
Insulated conductor without earthed
screen, bare conductor, or covered
conductor:
11, 22 and 33kV 7.3 6.0 5.0
66 and 132kV* 8.0 7.3 6.0
Table 3.5.6.6.1 – CEOM7097 Clearance from Ground for Overhead Lines other than Insulated
Service Lines

*66kV and 132kV clearances from ground shall be as nominated in CEOM7081- Subtransmission Line
Design Manual.

Notes:

1. For the purpose of this Clause, the term ‘ground’ includes any unroofed elevated area accessible
to plant or vehicles and the term ‘over’ means ‘across and along’.
2. In the case of cliff faces or cuttings the clearances specified in the column headed ‘Over land
which due to its steepness or swampiness is not traversable by vehicles’ shall apply.
3. In the case of waterways, flood plains and snowfields, the clearances should be determined having
regard to local conditions and requirements. Also refer to 3.5.15.2 Crossing of Waterways.
4. The above values are based on vehicles with a maximum height of 4.6 m.
5. Where the usage of land is such that vehicles of unusual height (more than 4.6m) are likely to pass
under an overhead line, the clearances given in this clause may need to be increased.
6. The distances specified are designed to protect supports from damage from impact loads on
conductors as well as protecting vehicles from contact with conductors.
7. Ground clearance over the carriageway of road includes a distance of up to 4 metres on either side
of formed surface. This note only applies when there is no physical boundary (such as formed
kerbing, barrier etc.) distinguishing the carriageway from other regions such as footways.
8. In special circumstances Essential Energy’s Contestable Design and Certification Team (Network
Design Group) may approve that the design ground clearance be reduced to that provided in
AS/NZS7000.
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9. This note applies to non-conductive communications cables only and to vehicles not exceeding
4.6m in height. The minimum ground clearance for non-conductive communications cables over
the carriageway of roads shall be 5.5m. The minimum ground clearance for non-conductive
communications cables over land other than the carriageway of roads shall be 4.9m.
10. This note applies to non-conductive communications cables only and to vehicles not exceeding
3.0m in height. The minimum ground clearance for non-conductive communications cables over
land which due to its steepness or swampiness is not traversable by vehicles shall be 4.5m.
11. In special areas such as near boat ramps, bridges, river crossings etc., a detailed risk assessment
(also refer to Clause 3.2) shall be conducted with reference to the relevant Australian/New Zealand
Standard to determine the appropriate clearance of the overhead line, insulated service line or
non-conductive communications cable.

Table 3.5.6.6.2 lists the minimum clearances from AS/NZS 7000.

Distance to Ground in Any Direction (m)

Over Land Other Over Land Which Due to
Nominal System Voltage Over the
than the its Steepness or
Carriageway of
Carriageway of Swampiness is not
Roads
Roads Traversable by Vehicles
Bare low voltage
5.5 5.5 4.5
(400/230 V) Mains
Insulated low voltage
5.5 5.5 4.5
(400/230 V) Mains
Insulated conductor without
earthed screen, bare
conductor, or covered
conductor:
11, 22 and 33kV 6.7 5.5 4.5
66 and 132kV 6.7 6.7 5.5
Table 3.5.6.6.2 – AS/NZS 7000 Clearance from Ground for Overhead Lines other than Insulated
Service Lines

Insulated overhead services: The minimum height of insulated overhead services, over any part of a
carriageway of a public road shall be 5.5 metres and in accordance with Note 3 of Table 3.4 in the
Service and Installation Rules of New South Wales. Where it is not practical to achieve this clearance, a
variation for approval may be sought from Essential Energy in accordance with CEOM7097 clause 3.2.1,
on the basis that the clearances stipulated in Table 3.4, Figure 3.4, and their associated notes, of the
Service and Installation Rules of New South Wales shall apply.

3.5.6.7 Standard Design Temperatures

The Essential Energy standard design temperatures for overhead lines are as provided below:

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Design Maximum Design Temperature for

Nominal Conductor Operating additional safety margin
Situation/Location Temperature* – Refer to clause 3.5.8 of
Voltage Type
(thermal rating) CEOM7097
Low All
All locations 65° C 100° C
Voltage conductors
11kV,
22kV & SC/GZ Where permitted 50° C 80° C
33kV
ACSR or
AAAC Minor Rural distribution
65° C 100° C
11kV, including backbone lines
22kV & CCT
33kV Town mains and Major
AAAC rural distribution 75° C 110° C
backbone lines
66kV & All All subtransmission
85° C 85° C
132kV** conductors locations

Table 3.5.6.7

*The design maximum operating temperature may be varied with approval from the Planning team. In
this case, the Design temperature for new conductors will be the approved maximum operating
temperature increased by 35° C for Aluminium conductors, or 30° C for steel conductors

**66kV & 132kV standard design temperatures and stringing tension requirements shall be as nominated
in CEOM7081- Subtransmission Line Design Manual.

3.5.6.8 Wind Return Periods and Design Wind Pressures

The Essential Energy wind return periods and design wind pressures for new lines at different locations
are shown in the table below. If a line is replaced, then it is treated as a new line.

Location Line Security level Design Working Life Wind Return Period.
Town mains Level III 50 years 200 years*
Main rural backbones Level II 50 years 100 years
Minor rural backbones
Level I 50 years 50 years
and spurs
Special circumstances Level III 50 years 200 years

Table 3.5.6.8.1

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Reference: AS/NZS7000 Table 6.1.

* For additional loads on existing town mains constructed prior to 2010 a Wind Return Period of 100
years can be applied.

Wind Pressure (Pa) for Regions A1-A7

Equipment Cd 50-year return 100-year return 200-year return
period period period
Steel, Composite, and concrete
1 925 1015 1102
round poles
Timber poles 1.3 1202 1320 1432
Octagonal poles 1.4 1295 1421 1542
Transformers 1.5 1387 1523 1653
Regulators 1.2 1110 1218 1322
Conductors* 1 925 1015 1102
Crossarms – End 1.2 1110 1218 1322
Crossarms – Wide face 1.6 1480 1624 1763
Insulators- Post/Pin 1.2 1110 1218 1322
Insulators- Strain/String 1.2 1110 1218 1322

Table 3.5.6.8.2

Wind Pressure (Pa) for Region B

Equipment Cd 50-year return 100-year return 200-year return
period period period
Steel, Composite, and concrete
1 1150 1380 1612
round poles
Timber poles 1.3 1495 1794 2095
Octagonal poles 1.4 1610 1932 2256
Transformers 1.5 1725 2070 2418
Regulators 1.2 1380 1656 1934
Conductors* 1 1150 1380 1612
Crossarms – End 1.2 1380 1656 1934
Crossarms – Wide face 1.6 1840 2208 2579
Insulators- Post/Pin 1.2 1380 1656 1934
Insulators- Strain/String 1.2 1380 1656 1934
Table 3.5.6.8.3

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Notes:

1. Cd refers to the drag coefficient. Cd values are derived from the HB 331 – Handbook Overhead
line design.
2. Drag coefficient for communication cables shall be obtained from the suppliers of these cables.
3. Conductors*- refers to conductor wind span. Tables 3.5.6.8.2 and 3.5.6.8.3 assume a Span
Reduction Factor (SRF) of 1 for downdraft wind regions and spans up to 200m. Refer to Section
B5.4.1, B5.4.2, Figure B5 and Figure B6 in Appendix B of AS/NZS 7000 for actual SRF to be
applied.

3.5.6.9 Line Angles of Deviation and Conductor Uplift

Where line angles of deviation occur, pin type insulators shall only be used where the side tension on the
insulators does not exceed 0.45kN per insulator under still air conditions at everyday temperature.

Where uplift occurs on a bare conductor from 11kV up to and including 33kV, a line post clamp top
insulator (catalogue number 263649) shall be used for conductor uplift up to 0.25kN. This would reduce
the number of through strain constructions required. Beyond a conductor uplift of 0.25kN, through strain
constructions shall be used.

3.5.7 Standard Overhead Conductors and Cables

Standard Overhead conductors and cables approved by Essential Energy for use in the overhead
network are described as follows:

3.5.7.1 Bare Overhead Line Conductors

The general principles for the use of bare overhead conductors on Essential Energy’s Distribution
networks are:

a. Low voltage – restricted usage only, i.e. LVABC or LV underground should be used wherever
possible. Approval is required from Essential Energy before installation of bare conductor. Refer to
Clause 3.2.1.

The bare low voltage neutral conductor shall be positioned consistent with the surrounding LV
network.

Low voltage spreaders are to be attached to all single phase and three phase bare LV approved
installations as follows:

• All spans up to 90 metres – One spreader mid span.

• All spans greater than 90 metres – Multiple spreaders are required, spaced up to 45 metre
intervals apart, depending on the span length. The spreaders are to be spaced at equal
distances along the span.

Construction plans are to show the number and location of LV spreaders that are to be installed in the
project.

b. 11kV, 22kV and 33kV – standard bare conductors should be used except where the area has been
identified as having a very high bushfire risk and assessment of the risk reduction using the value
appraisal framework shows a net benefit associated with the use of CCT for the affected spans.

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The use of CCT or other equivalent rated covered conductors should be evaluated where the spans are
located in:

• Areas of Essential Energy designated high bushfire risk e.g. P1 zones;

• Spans with high density vegetation or hazard trees, for reduced fire risk and/or reduced tree
clearing costs; OR
• Any other case where a positive cost benefit case, as determined by Essential Energy’s
Distribution Planning team, supports the installation.

Standard bare conductors are:

Essential Energy Stranding/Wire

Code Name
Catalogue No Diameter/Conductor Type
444060 3/2.75 SC/GZ * Refer note below
443220 3/4/2.50 ACSR Raisin
443910 7/3.00 AAAC Fluorine
443970 7/4.50 AAAC Hydrogen
440970 19/3.75 AAAC Neon
Table 3.5.7.1

* Note: Installation of 3/2.75 SC/GZ, galvanised steel conductor is not generally encouraged and will
require the Essential Energy’s approval prior to construction. Refer to Clause 3.2.1. The installation of
3/2.75 SC/GZ and 3/2.75 SC/AC will NOT be permitted within 50km of the coastline, or tidal waterways,
or within a 10km radius of an existing or planned zone substation in accordance with CEOP8003
Subtransmission and Distribution Network Planning Criteria and Guidelines. 3/4/2.50 ACSR is also not
be used within 50km of the coastline, due to the impact from salt environments.

3.5.7.2 Stay Wire

Essential Energy Catalogue No Description

600461 19/2.00 SC/GZ (Stay) 17m
600462 19/2.00 SC/GZ (Stay) 25m
600463 19/2.00 SC/GZ (Stay) 55m
600464 19/2.00 SC/GZ (Stay) 105m
600491 19/2.75 SC/GZ (Stay) 17m
600492 19/2.75 SC/GZ (Stay) 25m
600493 19/2.75 SC/GZ (Stay) 55m
Table 3.5.7.2

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3.5.7.3 Low Voltage Aerial Bundled Cable (LVABC)

LVABC is the standard overhead cable to be used throughout the Essential Energy LV networks.
Standard LVABCs are:

Essential Energy
Description
Catalogue No
445680 0.6/1kV 2-Core 25mm2 XLPE Stranded Aluminium LVABC
445710 0.6/1kV 4-Core 25mm2 XLPE Stranded Aluminium LVABC
447330 0.6/1kV 2-Core 95mm2 XLPE Stranded Aluminium LVABC
447420 0.6/1kV 4-Core 95mm2 XLPE Stranded Aluminium LVABC
447360 0.6/1kV 4-Core 150mm2 XLPE Stranded Aluminium LVABC
Table 3.5.7.3

3.5.7.4 High Voltage Covered Conductor (CCT)

CCT should be used in circumstances described in Clause 3.5.7.1 section b.

Standard HV CCT for use on Essential Energy’s distribution networks are:

Essential Energy
Description
Stock No
Cable 11kV 1 Core 40mm² (7/2.75) Stranded Al.
441120*
(AAAC/1120) XLPE (X-90) - GREY CCT
Cable 11kV 1 Core 80mm² (7/3.75) Stranded Al.
441130
(AAAC/1120) XLPE (X-90) - GREY CCT
Cable 11kV 1 Core 120mm² (7/4.75) Stranded Al.
441135
(AAAC/1120) XLPE (X-90) - GREY CCT
Cable 11kV 1 Core 180mm² (19/3.50) Stranded Al.
441140
(AAAC/1120) XLPE (X-90) - GREY CCT
Table 3.5.7.4

* 40mm² CCT is not a standard stringing conductor.

High Voltage CCT is an insulated unscreened conductor and does not require an earthing system to
maintain its integrity. However, the system requires Current Limiting Arcing Horn & Discharge Connector
(CLAH/DC) to divert surge energy, resulting from lightning strikes, to earth.

The CLAH/DC units are to be installed at intervals of not more than 400 metres giving a protection zone
of 200 metres either side of the unit installation. Surge diverters are to be provided on substations and at
underground to overhead interfaces.

3.5.7.5 Conductor Fittings

At intermediate locations/structures, conductors will be attached to insulators by various fittings or

combination of fittings including ties, armour rods, suspension clamps and vibration dampers where
applicable. Where damping is required, spiral vibration dampers should be used on bare overhead
conductors and CCT cables up to and including 7/4.50. Stockbridge or ‘dog-bone’ dampers are to be
installed on larger conductors.

Preformed dead-ends are to be used at all termination/strain points.

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For use of preform ties or hand ties, refer to CEOM7106.01.

General requirements are:

• Vibration dampers should be used on all spans where the design tension exceeds the ‘Rural All
Terrain No Dampers’ values of the conductor CBL given in Table 3.5.8.2.
• Vibration dampers should be used on all spans of SC/GZ, ACSR, AAAC (1120), Copper
conductors and CCT cables greater than 130 metres.
• The requirement for vibration dampers may be reduced in forest areas where the smooth laminar
airflow is broken by the vegetation profile.
• Refer to the Overhead Construction Manual for details on placement and fitting of vibration
dampers.
• Conductor uplift conditions must be avoided at all intermediate positions.
• Conductors less than 4.4mm in diameter do not require vibration dampers.

3.5.8 Standard Stringing for Overhead Conductors

Selection of conductor tension to be used on a project is generally a compromise due to the many
variable components. Geographic features (i.e. road formations, property boundaries, land profile, soil
properties, accessibility, vegetation, environmental considerations etc.) and not necessarily stringing
tensions will ultimately govern the positioning of most poles. Using higher tensions could result in fewer
and/or shorter poles but may require higher strength poles, crossarms, fittings, footings and stays and
might not prove to be the best overall economic, environmental, and maintenance-effective solution.
Reduced stringing tensions should be used where clearances can be achieved without the installation of
additional poles.

For overhead line design it is usual to use a tension at a reference temperature with no transverse wind
for design purposes. This reference tension is the long-term average tension in the conductor/cable and
is the recommended design tension listed in the following tables. The reference temperature normally
used throughout Australia is 15°C.

When calculating maximum sags for new conductors as per Table 3.5.6.6.1 of CEOM7097, allowances
shall be made for site, environmental and construction variations (e.g.: ground undulations, conductor
creep, pole movement, pole footing depth etc.) by:

• Safety margin as shown in clause 3.5.6.6.

• Using a higher design temperature for ground clearance assessment (Design Temperature for
Additional Safety Margin) than the design maximum operating temperature (thermal rating) as
shown in Table 3.5.6.7.

These allowances do not have to be applied to existing conductors which are being re-tensioned to the
design standard they were built to.

In the initial design process, unless indicated otherwise in the design brief, or the actual temperatures in
accordance with the definitions provided in AS/NZS7000 are available, the following conditions may be
used:

• For uplift conditions in Coastal and Western regions – 5˚C and in Tablelands and Ranges – 10˚C
• The serviceability limit states for sustained load conditions in South, Mid and North Coastal regions
15˚C and Far South Coastal and other regions 10˚C.

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For undercrossing designs of transmission or subtransmission lines, the minimum operating temperature
of Essential Energy conductors shall be taken as 5˚C, unless otherwise indicated in the design brief. The
maximum operating temperature shall be as per Clause 3.5.6.7 of this document.

For inter-circuit clearances, the upper circuit shall be assumed to be at maximum operating
temperature (see Clause 3.5.6.7) while the lower circuit is at ambient operating temperature.

• Ambient temperature value for summer is considered to be 35˚C with upper circuit at maximum
operating temperature (see Clause 3.5.6.7).
• Ambient temperature value for winter is considered to be 5˚C with upper circuit at maximum winter
operating temperature. The maximum winter operating temperature value can be obtained from
Network Design Engineering Manager for Essential Energy’s internal designs or Contestable
Design and Certification team for ASP designs.

Unless otherwise indicated in the design brief, for blowout calculations, the conductor is assumed to be
at 35˚C and under 500 Pa wind loads.

For overhead lines constructed along streets in urban areas, span lengths are normally restricted to less
than 100 metres for HV only and less than 50 metres for dual circuit HV and LV or LV only. In these
cases, high tensions provide little or no additional benefits. For urban areas, the recommended design
tensions for Essential Energy’s overhead distribution networks are provided in Table 3.5.8.1, for which
stringing tables are included in the Overhead Construction Manual.

Recommended Design Tensions as % CBL for Various Applications

Conductor Type Urban Commercial/ Urban Dense Semi-
Urban Residential
Industrial Residential Urban
AAAC (1120) Bare 3% 3% 3% 9%
AAAC (1120) CCT 4% 4% 4% 7%
LV ABC
4% 4% 4% 7%
Refer Note 1

Table 3.5.8.1

Use of mid-span joints on new constructions is not permitted unless prior approval is provided by
Essential Energy. Examples where approval may be considered include:

• Where external factors such as inability to obtain traffic control time slots on major roads, or
• The cost is grossly disproportionate to the benefit (i.e. the need to build hurdles).
• Approval for one mid-span joint per phase may be granted in situations where the maximum
conductor length on a new conductor drum (for e.g.: 3km per drum for Nitrogen conductor) is not
sufficient to cater to the maximum design strain section length.

No mid-span joints are allowed on spans crossing railway lines or roads.

Note 1:
General rules for installation of Low Voltage Aerial Bundled Cable (LVABC) as listed in Clause 3.5.7.3
are:

• In span tension joints are not permitted for new installations.

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• Maximum everyday final tensions shall not exceed the values indicated in Australia/ New Zealand
Standard AS/NZS3560.1:2000 LESS 2.5% and are as follows:
25mm² 2 core = 1.1 kN max
25mm² 4 core = 2.2 kN max
95mm² 2 core = 4.1 kN max
95mm² 4 core = 8.2 kN max
150mm² 4 core =13.0 kN max
• Tensions in excess of 7% CBL should be avoided if installing insulation piercing connectors (IPC)
in tension span, due to difficulty experienced in insertion of plastic wedges to separate cores.
Alternative in rural areas is to insert IPC’s into non-tension section.
• Vertical bonding will take place with a maximum of 2 parallel LV ABC cables of the same circuit at
substations, links, terminations, tee, and service connections. They must also be used at least
every 100metres.
For rural areas, the recommended maximum design tensions for Essential Energy’s overhead
distribution networks are provided in Table 3.5.8.2. In regions where, overhead lines may be subject to
snow/ice loading, special conditions as described in AS/NZS7000 Clause 7.2.3 shall apply.

Recommended Maximum Design Tensions as % CBL for Various

Applications
Conductor Type Rural All Terrain Rural All Terrain Fully
Rural Residential
No Dampers Damped
SC/GZ 6% 13.5% 26%
ACSR 6% 13% 23%
AAAC (1120) Bare 9% 17% 21.5% Refer note 2.
AAAC (1120) CCT 7% 11% n/a Refer note 3
LV ABC
7% 11% n/a
Refer Note 1

Table 3.5.8.2
Note 2: The maximum standard stringing tension for 19/3.75 AAAC shall be 17%.

Note 3: Maximum design tensions above 11% are not standard constructions. For tight stringing CCT
applications approved by the local Planning Manager, the highest allowable value of everyday working
tension is 15%. Refer to Clause 3.2.1.

3.5.9 Poles
Overhead power poles and their foundations should be designed in accordance with publication
AS/NZS7000, taking into consideration the following requirements:

3.5.9.1 Pole Foundations

Foundation design should be based on soil test information or an estimate of soil parameters which
should be recorded on the construction plan. As a general principle only, the minimum depth for an
unstayed pole in ground should be 0.8 metre plus one tenth of the pole length, but it is recommended
that pole foundation designs as established using an approved design program be provided with each
project.
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Essential Energy has a preference for not concreting pole footings. Alternatives to be considered are:

• Use a heavier pole (strength rating) to increase the circumference & soil-bearing area.
• Increase setting depth.
• Utilise specified backfill such as ‘crusher dust’.

All backfill materials are to be suitably compacted.

Where pole foundations must be concreted, then the concrete is to stop 450mm below ground line to
facilitate future pole inspections.

Concrete foundations for timber poles are not permitted, with the exception of rail crossing pole
foundations which are to be installed in accordance with the Rail Party document PYS 02 (RIC Standard:
EP10 01 00 05 SP) and CRN ET 002.

Non-electrical and civil works close to Essential Energy’s electrical network must be undertaken in
accordance with Essential Energy’s Electrical Safety Rules subject to specific accreditation
requirements. In addition to this requirement, the requirements of SafeWork NSW Code of Practice:
Work Near Overhead Powerlines and the Essential Energy Operational Procedure: Work Near Essential
Energy's Underground Assets CEOP8041 should be followed prior to undertaking any works.

Poles that are expected to have Underground to Overhead (UGOH) connections in the future and
therefore will need excavation in the vicinity should be designed to remove the need for temporary
supports so that there is no risk associated with not having temporary supports during UGOH installation
in the future.

3.5.9.2 Pole Staying

Designers shall consider the use of heavier rated line poles and foundations as an alternative to the use
of stays, in the design process.

Where pole stays are required, then the following should be taken into account:

• Ground stays are generally preferred to overhead stays due to cost and ongoing maintenance of
additional stay pole.
• Where access permits, ground stays are generally preferred to sidewalk stays.
• Sidewalk stays shall only be used to provide additional support for the pole footing. Refer to
Construction Manual drawing CEOM7103.05 for use of sidewalk stays.
• Ground stays should be avoided in stock (e.g. cattle and horse) paddocks due to the fact that stock
rubbing against stay wire can cause system operation problems. When alternate locations are not
possible a stay guard rail shall be used as shown in Essential Energy’s Overhead Construction
Manual drawing, CEOM7103.16.
• Screw anchors, where soil conditions permit, are preferred to baulks.
• Ground stays are not preferred in flood prone areas.
• Pole stays are not permitted on Ingal tapered multi-faced steel poles shown in drawings
CEOM7102.08, CEOM7104.07, CEOM7104.08, CEOM7104.09 and CEOM7105.01, unless a full
engineering design is completed including modelling for all pole stresses for the specific loads
being applied.

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3.5.9.3 Use of Temporary Stays

When the use of a temporary stay is required to support the load on a structure during new or
rectification works the following rules apply:

• If the structure to be supported has no stays currently applied, then a risk assessment shall be
performed to determine if a design assessment is required. The design assessment if deemed
necessary will detail where to apply temporary stays considering the loads placed on the structure
during the proposed work.
• If the structure has existing stays, then the temporary stays are to be fitted before removal of the
existing stays. The temporary stay heads are to be within 200mm of the existing stay head and the
temporary stays are to be in the same plane as the existing stays.
• If the application of temporary stays in accordance with the above dot point impedes work then a
design assessment will need to be performed to fit temporary stays in differing positions to that of
the existing stays, or the structure will need to have the mechanical load removed in order to
permit work.
• Drilling of holes to fit temporary stays in poles is not permitted, a wrap lock is to be utilised.
• The size of the temporary stay shall be in accordance with the load applied to it. The load capacity
of Essential Energy’s Standard stays is listed in section CEOM7103 of the Overhead Construction
Manual.

3.5.9.4 Pole Placement

Generally, when selecting pole locations consideration should be given to minimising the number of
poles to be installed without causing future encroachment problems and to locate poles to provide
ongoing access for maintenance and operations. A minimum clear space shall be provided around
network assets including pole substations, in accordance with the clearances required in Section 8 of the
Easement policy CEOP8046, irrespective of whether an easement exists at the site. All pole substations
shall be positioned in a location that allows access at all times by a crane borer/ erector.

Line routes should be selected so as to negate the need for road crossing (service) poles. Poles for low
voltage construction should generally be positioned every second property boundary so as to eliminate
service encroachments on neighbouring properties. Footpath allocations may also vary between Local
Government areas. Some poles (e.g. streetlight poles etc.) should ideally be placed near the property
alignment.

Poles in rural areas must not be installed too close to fences. Apart from the possible electrical hazards,
pole and line inspectors require an area around poles to allow for routine inspection. A minimum
separation of 1.5m is required between fence and pole.

Poles should be placed outside the Clear Zone so as not to pose a hazard to motorists. As per
AS/NZS1158.1.2 – ‘Vehicular Traffic (Category V) Lighting – Guide to Design, Installation, Operation and
Maintenance ‘, the Clear Zone is defined as “the area that begins at the edge of the travelled lane and is
available for emergency use by errant vehicles that run off the road. This zone includes any adjoining
lane/s, road shoulder, verge, and batter. Refer to applicable road controlling authority for clear zone
specifications”.

Pole setback zones can be divided into the following zones:

• Zone 1 – This zone lies closest to the outer edge of the traffic lane(s). This is the pole total
exclusion zone.

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• Zone 2 – This zone lies between Zones 1 and 3 and includes the clear zone, which is free of
hazards and specified by the applicable road controlling authority’s documents.
• Zone 3 – This zone is further most from the edge of the traffic lane and is outside the clear zone.

In case of greenfield sites, where possible, the Clear Zone distance shall be as set out in Table 4.1 and
associated notes of Austroads: Road Design – Guides; Part 6: Road Design, Safety and Barriers.
According to this guide, the minimum width of the Clear Zone required is 3m. However, in urban low-
speed areas, where it can be difficult to achieve these requirements a reduced Clear Zone of 1m may be
acceptable for established residential areas.

The widths of Zone 1 and 2 vary depending on road configuration. For example, straight sections are
different from intersections, islands, roundabouts, and bends. Zone widths also depend on the type of
embankment and whether there are safety barriers and/or other obstructions.

When calculating the width of Zones 1 and 2:

• The widths of Zones 1 and 2 (i.e., the Clear Zone) should be as set out in Table 4.1 and associated
notes of Austroads: Road Design – Guides; Part 6: Road Design, Safety and Barriers.
• Zone 1 starts at the inside edge of the kerb or at the edge of the traffic lane (for roads without
kerbs).
• If there is a kerb, the minimum width of Zone 1 is 0.7m as per AS/NZS1158.1.2.
• If there is no kerb, the minimum width of Zone 1 is 1m as per AS/NZS1158.1.2.
• In the vicinity of intersections, islands, roundabouts and bends the minimum width of Zone 1
required is 1m.

Refer to ‘Pole Setback Zones ‘, Section B6 of AS/NZS1158.1.2. Also refer to Austroads: Road Design –
Guides.

Dedicated Streetlight column/poles shall be positioned in accordance with the requirements of

CEOM7206.02, or the selection of an appropriate pole type and setback shall be commensurate with the
traffic hazard that will result in the safest possible lighting installation as per section 7.2.3 of
AS/NZS1158.1.2. Recommended minimum setbacks and pole exclusion zones from the kerb for various
traffic conditions and pole types are listed in Appendix B of AS/NZS1158.1.2.

Where a design or standard variation is required in order to achieve a required pole setback, such
request shall be referred to Essential Energy for approval. Refer to Clause 3.2.1.

3.5.9.5 Pole Type

At distribution voltages (LV, 11kV, 22kV and in some instances 33kV), the pole type chosen for new
constructions shall be timber. Specific high value/risk locations can also use composite poles as per the
next section on additional information on pole types that outlines composite poles selection criteria. The
use of concrete and steel poles for new constructions is not permitted.

Where prior approval is obtained for use of steel poles, their use is not permitted in soils with a soil
resistivity below 30 ohm-m due to galvanic corrosion issues in such soils.

Operational equipment (Note 1 of clause 3.5.9.5) can be added to an existing pole (whether timber,
composite, steel, or concrete) that is assessed to be acceptable to carry the additional loads based on
design assessment. In this instance there is no need to change the pole type to timber. It shall be
ensured that pole substations on steel poles are installed only after soil resistivity tests are done on site.
If the soil resistivity value is less than 100 ohm-m, only timber and composite poles shall be used due to
galvanic corrosion issues with steel substation poles in such soils.
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Notes:

1. For the purposes of this clause, Operational poles include poles with operational equipment such
as enclosed switches, single phase, and 3-phase reclosers, single phase and 3-phase substations
and links/EDOs but exclude SWER substations, SWER reclosers and regulators.
2. For SWER substations, SWER reclosers and regulators only timber and composite poles shall be
used.
3. Non-operational poles include single phase, 3-phase and SWER pin/angle poles.
4. Customer meter box/switchboard shall only be mounted on timber and composite poles.
5. Underground to Overhead (UGOH) terminations shall only be mounted on timber and composite
poles.

Additional information on pole types are as follows:

• Timber Poles: Timber poles are Essential Energy’s preferred pole type for distribution. The
strength and dimensions of timber poles for use in the Essential Energy distribution network shall
be in accordance with the information provided in section CEOM7101.03 and CEOM7101.06 of the
Overhead Construction Manual.
• Steel Poles: The strength and dimensions of steel poles on the Essential Energy distribution
network shall be in accordance with the information provided in section CEOM7102.08,
CEOM7104.07, CEOM7104.08, CEOM7104.09 and CEOM7105.01 of the Overhead Construction
Manual.
• Composite Fibre Poles: Sites currently evaluated as suitable are as follows, however the Design,
local Planning or Operations teams may choose other sites at their discretion:
• Locations with access restrictions or high cost to achieve accessibility
• Sugar cane crops that are burnt bi-annually
• Locations that have a known high termite impact
• Locations of swampy ground that have high levels of water for extended periods
• National Parks that have strict access requirements and regeneration policies
• Locations where bushfires have caused the same pole to be burnt more than once in the last
15 years.

Approval process for deviation from Clause 3.5.9.5:

Regional or depot deviations from the design manual requirements for the pole type may be permitted in
exceptional circumstances only after approval from the Asset Management and Engineering Group.

Case by case variations shall be assessed by Network Design Engineering Manager in the Asset
Management and Engineering Group, refer to Clause 3.2.1.

3.5.9.6 Supplementary Fittings to Poles and/or Conductors

Supplementary fittings, in addition to the normal standard fittings, will be required as indicated in the
following situations:

• Aerial inspection markers in accordance with EC guide for poles either side of any line crossing
• Aircraft warning markers fitted to overhead lines in proximity of authorised landing sites and
marking of overhead cable for low level flying in accordance with Australian Standard AS3891
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• Sighters/bird diverters fitted to overhead conductors in the vicinity of known wildlife corridors to
improve visibility of conductors
• LV spacers to each span of bare overhead low voltage conductor in accordance with Clause
3.5.7.1.

3.5.10 Timber pole assessment for additional loads

Where additional loads are proposed to be added to existing timber poles, a full engineering assessment
shall be carried out by a competent person to determine the suitability of the pole to carry the new loads.

All timber poles within the network are routinely inspected. This process records sufficient
measurements to calculate the available pole capacity. These measurements (wall thickness and
groundline diameter) and pole details can be sourced from the Asset Management System, however the
accuracy of these measurements cannot be guaranteed. Determining the pole’s estimated remaining
strength based only on these measurements is not a reliable means of determining the pole capacity for
a new design using existing poles. Users of this information are expected to exercise reasonable
professional practices in verifying the information provided. Basic checks and objective measurements
such as (but not limited to) confirming the pole details and the pole diameter to compare with the
provided information shall be performed to determine the pole capacity.

Adding new loads is not permitted in the following circumstances:

• Additional loads are not to be applied to a reinforced pole. This does not apply to work that
reinstates the loads to original design parameters, e.g. re-tensioning or staying.
• Additional loads are not to be applied to a pole classified as condemned or limited life as identified
in the Asset Management System.

The following standards, design parameters and design rules shall be applied when evaluating existing
poles:

• Australian/New Zealand Standard AS/NZS7000 shall be the applicable primary standard. Any
requirements specified by Essential Energy in this document (CEOM7097) shall prevail over the
corresponding requirements of AS/NZS7000.
• A Strength Reduction Factor (ǿ) of 0.5 is required as per Essential Energy Overhead Construction
Manual drawing CEOM7101.03.
• Wind loads and drag coefficients shall correspond to the values shown in clause 3.5.6.8 – Table
3.5.6.8.2 (Regions A1-A7) and Table 3.5.6.8.3 (Region B) as applicable for a 50 Year Design Life.
• Modifications to existing structures which will reduce the ground clearances of the overhead line
conductors below the values in clause 3.5.6.6.1 are not permitted.
• Where there are no structural modifications, ground clearances of the overhead line conductors
shall comply with the requirements in AS/NZS7000 Table 3.6 (including the associated notes for
Table 3.6).
• Ground clearances for any new or replacement pole shall comply with clause 3.5.6.6.1.
• The addition of new sidewalk stays on existing poles is prohibited.

The pole capacity shall be compared against the total (new) design load on the structure determined by
design assessment. If the pole capacity is more than the total design load on the structure, then the pole
shall be retained. If not, the pole shall be replaced.

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3.5.11 Distribution Substations

Distribution Substations are to be constructed in accordance with the requirements set down in Essential
Energy document CEOM7104 Construction Standard Manual.

Where a substation requires that a 200kVA or larger transformer be installed, and the substation is
shared by two or more customers, then Maximum Demand Indicators (MDIs) are to be installed on the
structure.

Distribution Transformer Fusing shall be in accordance with CEOS5099 Distribution: Transformer

Fusing.

Where a pole mounted substation is to be upgraded and the new transformer is of similar weight and
physical size to that which is to be replaced and the pole has been inspected and found to be in a sound
condition by Essential Energy, then the substation pole will not need to be replaced.

Only standard size transformers, listed as follows, are acceptable for connection to the network system.

Standard Pole-Mounted Distribution Transformer – Refer to Essential Energy’s Standard

Construction Manual, Sections CEOM7104.22 and CEOM7104.23 for further details.

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Single Phase Transformers Three Phase Transformers SWER Transformers

Essential
Essential Essential
Energy
kVA Voltage Energy kVA Voltage Energy kVA Voltage
Catalogue
Catalogue No Catalogue No
No
253700 16 11kV 254930 16 12.7kV
253940 16 22kV 255050 16 19.1kV
253730 25 11kV 252110 25 11kV 254960 25 12.7kV
253970 25 22kV 252980 25 22kV 255110 25 19.1kV
254100 25 33kV 254120 25 33kV
253790 50 11kV 254970 50 12.7kV
254030 50 22kV 255130 50 19.1kV
254032 50 33kV 252200 63 11kV
253070 63 22kV
254140 63 33kV
252290 100 11kV
253100 100 22kV
254150 100 33kV
252410 200 11kV
253160 200 22kV
254160 200 33kV
252590 315 11kV
253250 315 22kV
254170 315 33kV
252740 500 11kV
253310 500 22kV
254180 500 33kV

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SWER Isolating Transformers

Essential
Energy kVA Voltage
Catalogue No
255230 100 11/12.7kV
255260 100 22/12.7kV
255320 200 22/12.7kV
255408 100 22/19.1kV
255116 200 22/19.1kV
255420 250 22/19.1kV
255470 200 33/12.7kV
255490 100 33/19.1kV
255497 200 33/19.1kV
255478 250 33/19.1kV

3.5.12 Earthing
The design and construction of all earthing systems forming part of the works to be vested in Essential
Energy shall comply with CEOM7109 Construction Standard for Distribution System Earthing and
CEOM5113.02 High Voltage A.C. Distribution Earthing: Procedure.

All distribution network earthing designs shall be conducted and assessed using Essential Energy’s
distribution earthing design software package (Neutron). The Neutron software package is available
on request through neutron@essentialenergy.com.au

All substations are required to have an accompanying electrode type earthing system suitable for its
purpose.

The earthing electrodes for pole-mounted substations are generally installed in a dedicated roadway
or easement surrounding the pole base (if shared transformer on private property).

Special earthing designs and segregation limits may be required in situations relating to swimming
pools, communication centres, petrol, and liquid fuel centres etc. For the principles of earthing, the
principal guideline is CEOM5113.02.

In locations where staff may be required to operate pole mounted equipment, the earthing should
comply with the requirements of CEOM5113.02.

3.5.13 Protection of Overhead Networks

3.5.13.1 High Voltage Overhead Networks

Protection of all overhead high voltage distribution feeders will be provided by Essential Energy at the
source substation by relays and circuit breakers and at positions along the feeder by reclosers and
other protective devices in accordance with CEOP8002 Essential Energy: High Voltage Protection
Guidelines.

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Note: CEOP8002 is not a public domain document.

a. 11kV/22kV Feeders

These feeders will normally be provided with the following:

• 3-phase overcurrent
• earth fault
• instantaneous overcurrent and earth fault
• sensitive earth fault
• an earth fault indicator.

Reclosing will be provided at the source substation and initiated by all protection other than sensitive
earth fault. Automatic reclose timing and automatic reclose attempts shall be in accordance with
CEOP8002.

Reclosing should be rendered non-operative during:

• Switching between feeders

• Live line work
• Tree trimming
• High fire danger days on bushfire designated feeders.

Back up protection will be provided by one of several options. This protection will improve limitations
in the design of the feeder configuration as follows:

• A minimum conductor size will be nominated by Essential Energy for a particular feeder
depending on fault levels, protective clearing times and load capacity. This also applies to any
underground cable connected and to the cable sheath
• A maximum feeder impedance will be specified by Essential Energy to ensure minimum fault
levels at feeder extremities are adequately detected by protection including back-up protection.
All designs must account for these aspects and will be checked for compliance.

b. Line Reclosers

Pole-mounted line reclosers will be used in overhead distribution feeders where nominated by
Essential Energy. Line reclosers will be of a type complying with Essential Energy’s specification
and will provide protection, reclosing, and remote control (SCADA) facilities.

c. Line Sectionalisers and Line Fuses

Line Sectionalisers and line fuses may occasionally be used on 11kV and 22kV feeders, but
their use is kept to a minimum.

3.5.13.2 Protection of Low Voltage Overhead Networks

All 400/230V overhead bare conductor or aerial bundled conductor (ABC) networks are to be
protected by current limiting HRC fuses at the distribution substation.

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Fuse types and application are to be in accordance with Essential Energy’s Fuse Standard document
CEOS5099. The fuse size to be used will be nominated by Essential Energy’s local Planning team for
the region in which the installation is to be carried out and in accordance with the above documents.

Note: CEOS5099 is not a public domain document.

The maximum rating fuse to be used on an overhead low voltage network or distributor is 400A and all
fuses shall be fast characteristic as defined in CEOS5099. Small rating distributor fuses shall be used
in small transformer installations as defined in CEOS5099.

There are limitations on the use of ABC conductors for protection reasons. The maximum impedance
of LV network to the extremity of the ABC conductor is defined in Table 3.5.13.2 and associated
notes.

Max Loop Max Distributor Length

Fuse Size Impedance for the
Distributor 1 x 95 2 x 95 1 x 150

400A 160 + j32 mΩ 200m 400m 300m

250A 280 + j56 mΩ 350m 700m 530m
100A 720 + j144 mΩ 900m - 1360m

Table 3.5.13.2

Notes for Table 3.5.13.2:

1. Standard fuse sizes are in accordance with document CEOS5099

2. The loop impedance of a LV distributor is defined as the total impedance, measured from a
Distribution Centre to the network extremity, of a phase conductor plus the return neutral or
other phase conductor
3. The maximum distributor length is for protection limitations and does not take into account
voltage drop considerations. That is, voltage considerations may considerably reduce the
distributor length
4. The intention is to clear the worst possible faults in approximately 10 seconds. Fuse clearing
times are based on the slowest characteristic compatible with Essential Energy’s specified
bandwidth for fuse time-current characteristics
5. The maximum distributor length provided in Table 3.5.13.2 could be exceeded for a particular
situation provided that the 10 second clearing time is maintained
6. The distributor lengths provided are based on the maximum loop impedance for a distributor
with a constant cable configuration, i.e. 1 or 2 cables per phase for their entire length. Where a
mixed configuration is used an equivalent proportional length can be used, e.g., 200m of parallel
95mm2 cable plus 100m of single 95mm2 cable for a 400A fuse (see figure 1 below).

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Figure 1 – Mixed Cable Configuration

3.5.14 Insulation Co-ordination

In general, Essential Energy’s overhead line designs and standards are based on co-ordinated levels
of insulation withstand voltages for the various line configurations and equipment types together with
the correct application of surge arresters.

Failure performance of the installation is very adversely affected by seemingly minor departures from
construction standards affecting clearances or configuration.

The basic insulation coordination principles and application guidelines as detailed in the IEC 60071
standards series should be applied to all overhead lines and associated equipment.

It is important that all material and equipment installed on the network comply with the appropriate
Essential Energy Specification.

Principles to be followed are:

• Every pole substation to have surge arresters at the transformer HV terminals.

• Every HV underground to overhead connection shall have surge arresters fitted.
• All surge arresters must comply with Essential Energy’s specifications and AS1307 and shall in
particular comply with the specification in respect to:
• Spark performance.
• Shattering performances.
• Surge arresters are to be installed on both the source and load side of line reclosers,
sectionalisers and enclosed switches.
• No surge arresters are to be installed at inline air brake switch or link locations.
• Earthing systems shall comply with the requirements shown in CEOM7109 Construction
Standard for Distribution System Earthing and CEOM5113.02 High Voltage A.C.
Distribution Earthing: Procedure
• Pin insulators on timber crossarms are not to be bonded together (as this reduces BIL and
does not take advantage of the arc-quenching properties of timber).
• All 11kV lines shall be constructed with 22kV insulation except for lines located in salt
areas.

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• Additional insulation is required for lines constructed within 3km of the ocean or large
areas of saltwater including bays, inlets, and lakes, or where insulators are attached to
earthed/conductive poles and crossarms. For these areas, insulators achieving a ‘very
heavy’ pollution level rating as per AS 4436 specifications will be required. For 11kV and
22kV lines in these areas, the insulators provided in CEOM7101.05 shall be used. For
33kV lines the designer should seek advice from Essential Energy’s Network Design
Engineering Manager for the insulators to be used.

3.5.15 Special Requirements of Other Authorities

As previously indicated in Clause 3.2 of this document, it is the responsibility of the designer to obtain
approvals as necessary from other relevant authorities prior to construction. As a general requirement,
all crossings of rail lines, waterways, TransGrid undercrossings and overhead lines near aircraft
landing fields MUST be profiled. Basic requirements are as follows:

3.5.15.1 Rail Crossings

Essential Energy’s electrical network extends over or near the property of the following rail authorities:
• Australian Rail Track Corporation (ARTC)
• Transport for New South Wales (TfNSW) Country Regional Network – Managed by John
Holland Rail (JHR)
• Queensland Rail
• Victrack
• V/Line

Where a network project involves work on rail property or where the work will affect rail property, the
designer must submit an Access Application as per the requirements of the local rail authority. An
Access Application has two main purposes:
1. Obtain rail authority consent, including the terms and condition of access, to enter and work
within the rail corridor; and
2. Obtain technical approval from the rail authority for the design and/or construction of network
assets, on or near the rail property.
For a design to be certified, it must comply with both Essential Energy’s Design and Construction
Standards, and the rail authority’s technical specifications (such as ARTC’s PYS 02 or John Holland
Rail’s CRN ET 002). The rail authority’s technical specifications may vary from the requirements of
Essential Energy’s Design and Construction Standards.

Essential Energy internal designers must comply with the following Essential Energy documents when
accessing the rail corridor (does not apply to ASPs).
1. CEOP2407 – NSW Rail Corridor: Essential Energy Access
2. CEOP2134 – NSW Rail Corridor: Work Safety Protocol
3. CEOP2135 – NSW Rail Corridor: Emergency Event Plan
4. CEOP2136 – NSW Rail Corridor: Maintenance Plan for Essential Energy Facilities
Note: Low voltage (230/400V) aerial crossings of electrified tracks are NOT permitted.

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3.5.15.2 Crossings of Waterways

Like Rail Crossings, the accredited designer shall prepare a separate drawing with a profile of the
waterway crossing suitable for submission to NSW Roads and Maritime Services and the Crossing
Controller. The plan and profile shall include all details of the crossing such as pole heights, pole
locations in relation to the waterway, the relative levels of pole, conductor sag and clearance relative
to Australian Height Datum (AHD) for both non-tidal and tidal navigable waters at maximum design
operating temperature. Note that in the case of tidal waterways the highest astronomical tide (HAT)
level is required in the calculation in addition to wave effects, the mandatory minimum safety margin of
2.2m and the electrical flashover clearance as noted in AS6947 Table 3.1.

NSW Roads and Maritime Services requirements are set out in their document – Crossings of NSW
Navigable Waters: Electricity Industry Code which is to be read in conjunction with Australian
Standards AS6947 – Crossing of Waterways by Electricity Infrastructure. Essential Energy
requirements are also noted in document CEOP2013 – Crossings of Navigable Waterways.

Accredited designers shall advise Essential Energy of any proposed waterway crossing prior to
submitting an application to NSW Roads and Maritime Services.

It will be the designer’s responsibility to organise the appropriate signage and the erection of the signs
in accordance with NSW Roads and Maritime Services and Essential Energy’s requirements.

3.5.15.3 TransGrid Undercrossings

Like Clause 3.5.15.1 the accredited designer shall prepare a separate drawing of all undercrossings of
TransGrid lines. The drawing shall provide a plan and profile showing details of the poles and
conductor heights and location of the undercrossing in relation to TransGrid conductors and
structures. Reference is made to TransGrid drawing A3 TL613883 for the clearance requirements.

The height of TransGrid conductors should indicate the time, the day, month and year and the
ambient temperature at which the measurement was taken with appropriate notation of any wind
condition present at the time.

The maximum height of Essential Energy lines shown on the profile shall be the minimum designed
operating temperature of the line.

Air navigation disc markers are to be installed in accordance with AS/NZS3891.2 and Essential
Energy drawing CEOM7106.10.

The ASP is responsible for arranging all necessary approvals from TransGrid including completion
and submission of all the applications and paperwork required for approvals. If required, Essential
Energy’s regional office may provide assistance with any information that might assist the ASP.

3.5.15.4 Overhead Lines Near Aircraft Landing Fields

Designers should be aware that overhead power lines shall not encroach on glide paths adjacent to
aircraft landing field. There are three types of aerodrome listed by the Civil Aviation Safety Authority,
certified aerodromes, registered aerodromes, and rural aerodromes.

Glide path dimensions and clearances from obstructions for certified and registered aerodromes are
provided in CASA document ‘Manual of Standards CASR Part 139 chapter 7’ located on CASA
website.

The list of certified and registered aerodromes can be found on CASA website.

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Glide path dimensions for rural aerodromes are provided in Civil Aviation Authority Publication
CAAP92-1(1) located on CASA website.

Fitment of aircraft warning marker balls to conductors and OHEWs located near aircraft landing fields
may be required, refer to section 3.5.9.5. Designers should increase the wind loading on conductors
accordingly if warning marker balls are to be fitted.

3.5.15.5 Co-ordination of Power and Conductive Telecommunication Cables/Systems

Guidelines for the co-ordination of power systems and conductive cable telecommunication system
requirements are provided in Standards Australia document AS/NZS3835.1 – Earth potential rise –
Protection of telecommunications network users, personnel, and plant – Code of practice. Deviation
from AS/NZS3835.1 is permissible only after design evaluation. Also refer to HB100 (CJC4) – Co-
ordination of Power and Telecommunication. All designs shall comply with the requirements of the
aforementioned guidelines.

3.5.15.6 Overcrossing or Undercrossing of Essential Energy lines (e.g.: Solar farm, Wind farm
lines)

For projects involving overcrossing or undercrossing of Essential Energy’s distribution lines by utility
or private lines, consultation must be carried out with Essential Energy‘s local Planning team. The
general guidelines for the form of construction for each project shall be determined and will be in
accordance with the prevailing policy of the time as communicated by the local Planning team. As far
as practicable, all crossings shall be perpendicular to the Essential Energy line. All overhead line
crossings shall conform to AS/NZS 7000 and HB331. The party pursuing the over/undercrossing
should cover any costs incurred by Essential Energy while the work is being carried out.

Air navigation disc markers are to be installed in accordance with AS/NZS3891.2 and Essential
Energy drawing CEOM7106.10.

3.6 Load Types and Values

Customer Utilisation
Load Types and Values Table Factor of Transformer
Sizing
Standard No of Utilisation
Region Load Type ADMD Deviation customers Multiplier
Ratio
Units and Relocatable
3.0kVA/dwelling 1.0
Homes
1 2.0
Prestige Units,
3.5kVA/dwelling 1.0
Integrated Housing
All
Rural Estates 7.0kVA/lot 1.0 2 1.60

Light Industrial Estates** 30.0kVA/lot** 0 3 1.47

Pumps and Motors Actual Rating 0 4 1.40
Coast Residential* 4.0kVAlot* 1.0 5 1.36
Prestige Housing, Canal
Coast Estates, Village 5kVA/lot 1.0 10 1.25
Residential

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Customer Utilisation
Load Types and Values Table Factor of Transformer
Sizing
Standard No of Utilisation
Region Load Type ADMD Deviation customers Multiplier
Ratio
Prestige Residential – no
Inland 7.5kVA/lot*** 1.0
reticulated gas***
20 1.10
Residential – no
Inland 6.0kVA/lot 1.0
reticulated gas
Residential – reticulated
Inland 4kVA 1.0
gas
30 1
Prestige Residential
Inland 5.5kVA 1.0
reticulated gas
* Includes Duplex Lots

** Use 30kVA or actual known loading, whichever is greater

*** In some prestige Alpine residential subdivisions or in other specific locations, it may be prudent
to use an ADMD greater than 7.5kVA/lot. In such cases the actual ADMD used will be
identified in the preliminary design information.

In addition to the previous load information, when calculating voltage drops using ‘LVDROP’ (version
5.48 or later) software, the following parameters should also be used.

Transformer : LOIMP
Voltage :
Source = 240V
Nominal = 230V
Confidence Factors for Overhead Systems:
Voltage Drop = 2.00
Conductor Loading = 2.00
Transformer sizing use Utilisation Factor Table above.
Method Statistical
POA All Point of Application factors are to be calculated
Load Power Factor: Use 0.9 if not known
Node 3 phase total load: Use unbalanced multiplier of 1.
Node split phase: Use 1.5 times the distance as per the software
instructions.
Node single phase: Use twice (2 x) the distance as per the software
instructions.

SIZING OF TRANSFORMERS:

Where customer loads are not assessed using AS/NZS3000 and the tabulated ADMD values are
used, then the utilisation multiplier must be used in assessing the transformer capacity for the required
number of customers.

TRANSFORMER SIZE = ADMD x NUMBER OF CUSTOMERS x UTILIZATION FACTOR

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As a general rule, the transformer size obtained using this method should be in the order of 50% of
the value that would be obtained using the total load current shown in the LVDROP program.

3.7 Load Density Values for Assessment of Maximum Demand

Typical Load Density Values (VA/m2) for different types of Floor Area Usage (Net Areas)

These load density values depend on many factors including:

• the effects of the outside environment on the building structure and type of air conditioning
system
• the effects of heat or electrical equipment loads within the premises
• the proposed lighting design and
• the degree of environment control and load management within the premises.

Where insufficient information is available, reference is made to AS/NZS 3000 Table C3 Maximum
Demand--Energy Demand Method for Non-Domestic Installations.

Note: Medium and heavy industrial areas require full details of connected load before an assessment
of demand can be made. Only uniformly distributed loads such as lighting and air conditioning can be
assessed using this area usage method.

3.8 Conductor Information

Impedance values show in the following conductor information table are provided for calculating
purposes only and should be used when assessing existing networks for interconnection with new
developments using standard conductors. In general, the impedance R and X components and the
conductor ratings are extracted (where available) from the Australian/New Zealand Standard
AS/NZS3008.1.1. Generally, resistance values are for a conductor temperature of 75°C and the
Reactance values are for LV conductor spacing of 0.6m at 50Hz. The current carrying capacity of the
conductors shown are generally based on an ambient temperature of 40°C and a maximum conductor
temperature of 75°C with a wind speed of 1m/s. The values shown in the following table generally
align with those provided in the Essential Energy version of ‘LVDROP’.

CONDUCTOR INFORMATION TABLE

Conductor Size Resistance Reactance Rating
Description
and Type ohm/km ohm/km Amp
[AAAC-4W]
3Ø 4 WIRE LV 19/3.25AAAC 0.22544 0.29063 473
ALL ALUMINIUM 19/3.75AAAC 0.17123 0.28166 562
ALLOY BARE 19/4.75AAAC 0.11061 0.26684 747
OVERHEAD 37/3.00AAAC 0.13846 0.27389 642
CONDUCTOR 7/2.50AAAC 1.01631 0.34195 184
7/3.00AAAC 0.70735 0.33049 234
7/3.75AAAC 0.45175 0.31619 307
7/4.50AAAC 0.31505 0.30501 383
7/4.75AAAC 0.28307 0.3014 409
[AAC-4W]
3Ø 4 WIRE LV 19/.128AAC * 0.21817 0.2908 479
ALL ALUMINIUM 19/.149AAC * 0.16299 0.28126 570
BARE 19/3.25AAC 0.21937 0.29063 479
OVERHEAD 19/3.75AAC 0.16602 0.28183 570
CONDUCTOR 19/4.75AAC 0.10776 0.26684 756
37/3.00AAC 0.13541 0.27389 651
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CONDUCTOR INFORMATION TABLE

Conductor Size Resistance Reactance Rating
Description
and Type ohm/km ohm/km Amp
7/.118AAC * 0.68367 0.33055 237
7/.134AAC * 0.53037 0.32256 274
7/.144AAC * 0.43859 0.31821 311
7/.173AAC * 0.31943 0.30651 388
7/1.75AAC 2.02037 0.36437 139
7/2.50AAC 0.98472 0.34195 190
7/3.00AAC 0.68485 0.33049 237
7/3.75AAC 0.43859 0.31619 311
7/4.50AAC 0.3071 0.30501 388
7/4.75AAC 0.27615 0.3014 413
* Existing Imperial Size Conductors
CONDUCTOR INFORMATION TABLE (continued)
Conductor size Resistance Reactance Rating
Description
and type ohm/km ohm/km Amp
[ACSR-4W]
3Ø 4 WIRE LV 3/4/.0661 * 4.22584 0.39528 85
ALUMINIUM 3/4/.093 * 2.22801 0.37382 131
CONDUCTOR 3/4/1.75 4.06991 0.39208 85
STEEL 3/4/2.50 1.99131 0.37026 131
REINFORCED 4/3/3.00 1.16642 0.34834 91
4/3/3.75 0.74553 0.33404 238
6/1/.093 * 1.41429 0.34656 167
6/1/.118 * 0.87852 0.33159 209
6/1/.144 * 0.59083 0.31908 274
6/1/2.50 1.2674 0.343 167
6/1/3.00 0.88034 0.33154 209
6/1/3.75 0.56387 0.31752 274
6/4.75+7/1.60 0.36364 0.30244 364
[HDBC-4W]
3Ø 4 WIRE LV 19/.064HDBC * 0.54705 0.34839 270
HARD DRAWN 19/.083HDBC * 0.32147 0.31802 337
BARE COPPER 19/.101HDBC * 0.21753 0.30569 552
CONDUCTOR 19/1.75HDBC 0.4643 0.32973 286
19/2.00HDBC 0.35679 0.32134 337
19/3.00HDBC 0.16103 0.29586 552
7/.064HDBC * 1.44252 0.369 156
7/.080HDBC * 0.92372 0.35498 183
7/.104HDBC * 0.54705 0.33849 270
[ABC-2W]
1Ø 2 WIRE 25ABC/2c 1.41762 0.089 105
LVABC 95ABC/2c 0.37863 0.08 230
[ABC-4W]
3Ø 4 WIRE 25ABC/4W 1.41762 0.097 97
LVABC 50ABC/4W 0.75725 0.093 140
70ABC/4W 0.52418 0.088 175
95ABC/4W 0.37863 0.087 215
150ABC/4W 0.24449 0.084 280
* Existing Imperial Size Conductor
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4.0 AUTHORITIES AND RESPONSIBILITIES

Position / Title Responsibility

Manager Asset Engineering • Approving the design manual including any
variations;
• Making all decisions concerning compliance in
respect to this manual; and
• Delegating any of these authorities and
responsibilities to the Network Mains Engineer.

Manager Mains Standards and • Reviewing the manual and making

Specifications recommendations to the Manager Asset
Engineering; and
• Making recommendations concerning compliance
in respect to this manual.

Principal Engineer Overhead • Clarifying all the technical aspects of this manual
Construction Standards to the stakeholders;
• Approving the relevant actions required; and
• Summarise responsibilities allocated to employees
(by job/position title) within the process specified
under Actions.

Network Design Engineering • Clarifying the relevant technical aspects of this

Manager manual to the stakeholders;
• Approving the relevant actions required

Design Certification Officer • Clarifying the relevant technical aspects of this

manual to the stakeholders;
• Approving the relevant actions required

5.0 DEFINITIONS

ASP – Accredited Service Provider

An individual or entity accredited through a ministerially recognised accreditation scheme to undertake
contestable work. The three ASP levels are listed below:

• Level 1 - Construction of network assets.

• Level 2 - Service work/connection services.
• Level 3 - Design of network assets.

Customer
An entity or individual who is an end-user of electricity.

Developer
Developer, Customer, Contractor or Accredited Service Provider working on behalf of the developer,
other than Essential Energy Networks.

Distribution
For the purpose of this document is nominally Low Voltage, 11,000, 22,000 and 33,000 Volts.

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High Voltage
For the purpose of this document is nominally 3.3kV, 6.6kV, 6.9kV, 11000, 12700, 19100, 22000 and
33000 Volts.

Low Voltage
For the purpose of this document is nominally 400/230 Volts.

Street lighting Customer

The Body controlling the standard of lighting and responsible for the applicable Street Lighting
charges. For dedicated roadways, the Street Lighting customer is the NSW Roads and Maritime
Services or the Local Council and for Community Land Title developments under the Community Land
Development Act, 1989 it is the Community Association responsible for that particular development.

Subtransmission
For the purpose of this document is nominally 33,000, 66,000, 110,000 and 132,000 Volts.

Unclassified
Unrestricted within Essential Energy.

6.0 REFERENCES

Internal
HSE Manual: Management System Core Components- CECM1000.01
SHE Manual: Hazardous Materials – Responsibilities- CECM1000.10
HSE Manual: Environmental Impact Assessment NSW- CECM1000.70
HSE Manual: Environmental Impact Assessment QLD- CECM1000.71
HSE Manual: Land Use- CECM1000.76
HSE Manual: Cultural and Heritage- CECM1000.79
HSE Manual: Handbook- CECM1000.90
Environmental Impact Assessment: Screening Worksheet- CEOF1070.01
Review of Environmental Factors Worksheet- CEOF1070.02
Consultant checklist: Preparation of Review of Environmental Factors (REF) - CEOF1070.03
Pole Maintenance: Advice of Pole Maintenance Form CEOF6586
Network Services: Design Construction Drawings- CEOM7001
Standard Overhead Conductor: Current Rating Guide- CEOM7011
High Voltage A.C. Distribution Earthing- CEOM5113.02
Underground: Design Manual- CEOM7098
Overhead Construction Manual- CEOM7099
Pole Substation Service Connection to Distribution Substations- CEOM7104.27
Conductor Stringing Data 11, 33, 33kV & SWER- CEOM7106.01
Distribution Overhead Mains – Lighting- CEOM7107
Operational Procedure: Company Procedure - WHSE Safe Design- CEOP1000.27
Security: Information Sensitivity Labelling and Handling- CECP1096.01

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Internal
Vegetation Clearing Guidelines for New Power Lines- CEOP2010
Crossings of Navigable Waterways – CEOP2013
General Terms and Conditions: Supply of Electricity to New Subdivisions and Site Developments-
CEOP2015
Vegetation: Removing Vegetation near Overhead Powerlines- CEOP2021
NSW Rail Corridor: Work Safety Protocol- CEOP2134
NSW Rail Corridor: Emergency Event Plan- CEOP2135
NSW Rail Corridor: Maintenance Plan for Essential Energy Facilities- CEOP2136
NSW Rail Corridor: Essential Energy Access- CEOP2407
Company Policy: Procurement- CECP0009.04
Company Procedure – Policy and Procedure Framework (Business Management System):
Preparation and Amendment of Documents- CEOP4001.02
Contestable Work: Design Information Application – CEOF6010
Essential Energy: Distribution Protection Guidelines- CEOP8002.02
Subtransmission & Distribution: Network Planning Criteria & Guidelines- CEOP8003
Vegetation Management Plan- CEOP8008
Bush Fire Risk Management Plan- CEOP8022
Operational Procedure: Work near Essential Energy’s Underground Assets- CEOP8041
Networks: Asset Identification and Operational Labels- CEOP8042
Network Planning: Easement Requirements- CEOP8046
Connection Process: For Negotiated High Voltage Retail Customer Connection and Embedded
Generators >30kW- CEOP8079
Distribution: Transformer Fusing- CEOS5099
Subtransmission Line Design Manual- CEOM7081
Electrical Safety Rules – CEOP8030

External
AS1158 – Australian Standard Publication – Road Lighting Operation and Maintenance
AS1307 – Australian Standard Publication – Surge Arrestors
AS1824.1 – Australian Standard Publication – Insulation Co-ordination
AS2187.2 – Explosives—Storage and use – Part 2: Use of explosives
AS 3891 series – Air navigation – Cables and their supporting structures – Marking and safety
requirements. Part 1 and Part 2.
AS5577 – Australian Standard Publication – Electricity network safety management systems
AS6947 – Crossing of Waterways by Electricity Infrastructure
AS61000 – Australian Standards Publication – Electromagnetic Compatibility (EMC)

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External
AS/NZS3000 – Standards Australia/Standards New Zealand Publication – Wiring Rules
AS/NZS3008.1.1 – Electrical Installation – Selection of Cables
AS/NZS3012 – Electrical installations — Construction and demolition sites
AS/NZS3835.1 – Earth potential rise – Protection of telecommunications network users, personnel,
and plant – Code of practice

AS/NZS7000 – Overhead line design

Austroads: Road Design – Guides
CAAP 92-1(1) – Civil Aviation Authority Publication
CASR Part 139 chapter 7 – Manual of Standards – CASA Document
Community Land Development Act 1989
CRN ET 002 – Requirements for Electric Aerials Crossing CRN Infrastructure
Environmental Planning and Assessment Act 1979
HB100 (CJC4) – Australian Standard Publication – Co-ordination of Power and Telecommunications
HB331 – Handbook Overhead line design
ISSC20 –Guideline for the Management of Activities within Electricity Easements and Close to
Electricity Infrastructure
NSW Roads and Maritime Services – Crossings of NSW Navigable Waters – Electricity Industry
Code
PYS 02 – Requirements for Electric Aerials Crossing ARTC Infrastructure
Service and Installation Rules of New South Wales
Work Health and Safety Act 2011
Work Health and Safety Regulation 2017
Safework NSW Code of Practice: Work Near Overhead Powerlines
Safe Design of Structures Code of Practice July 2012
IEC 60071 – Insulation co-ordination

12 August 2020 – Issue 19

Approved By: Principal Engineer Overhead
Next review date: August 2023
Page 47 of 48
UNCLASSIFIED UNCONTROLLED COPY IF PRINTED
 Division Manual: Overhead Design Manual
UNCLASSIFIED CEOM7097

7.0 RECORDKEEPING

The table below identifies the types of records relating to the process, their storage location and
retention period.

Type of Record Storage Location Retention Period

Construction plans, ProjectWise Retain minimum of 7 years after
complete with any disposal or decommissioning of the
alterations asset, or where the project is not linked
to a specific asset or infrastructure
component, 7 years after action
completed, then destroy).GA40-6.4
Software Design Criteria ProjectWise/SharePoint Retain minimum of 7 years after
online disposal or decommissioning of the
asset, or where the project is not linked
to a specific asset or infrastructure
component, 7 years after action
completed, then destroy).GA40-6.4
Designer Safety Report SharePoint online Retain minimum of 7 years after
Check List (CEOF6489.05) disposal or decommissioning of the
asset, or where the project is not linked
to a specific asset or infrastructure
component, 7 years after action
completed, then destroy).GA40-6.4
Project Safety & SharePoint online Retain a minimum of 10 years after
Environment Plans superseded, then destroy. GA40 4.1
Approved copy of the BMS Retain a minimum of 10 years after
network standard superseded, then destroy. GA40 6.20

8.0 REVISIONS

Change
Issue
Section Details of Changes in this Revision Risk
No.
Impact?

3.5.6.5 Additional paragraphs added.

3.5.6.8 Tables 3.5.6.8.2 and Table 3.5.6.8.3 – Composite pole added

Undercrossing designs of transmission and subtransmission lines.

3.5.8
Wording revised.

19 3.5.9.5 Section revised. Composite fibre poles requirements added. Low

Confidence Factor for overhead systems voltage drop revised in

3.6
Table.
Change to Standard reference, now IEC 60071
3.5.14 Update of last two dot points in the principles to be followed
section.

All Update to new template

12 August 2020 – Issue 19

Approved By: Principal Engineer Overhead
Next review date: August 2023
Page 48 of 48
UNCLASSIFIED UNCONTROLLED COPY IF PRINTED