EARTHING DESIGN, PROTECTION & TESTING

EARTHING DESIGN OVERVIEW

APD Engineering’s electrical earthing design team have proven to be the industry leader through providing innovative and value adding services to clients. Our specialists have been actively involved in national and international technical societies, sponsoring events, presenting papers, hosting webinars and chairing Australian CDEGS User Group.

We also have an alliance partnership with the CDEGS developer, SESTech Pty Ltd, who are the world Leader in all aspects of Earthing, Lightning and Electromagnetic Interference. APD’s agreement with SESTech is liaison and technical support on Australian-based projects, sharing study improvements and technical papers and working collaboratively as needed on high risk critical projects.

Our earthing team consists of CDEGS accredited users who have proven experience in Greenfield and Brownfield projects and have completed detailed design and field testing activities for a wide range of clients from utility (Generation, transmission and distribution) through to mining, land development and railway sectors.

INDUSTRY ENGAGEMENT

APD are active members of a number of industry panels throughout Australia and this ensures that we not only keep up to date with the latest policy and technical design standards but it also presents us with an opportunity to provide our input and recommendations on any proposed changes. Some of the industry memberships that APD currently hold are listed below:

Urban Development Institute of Australia (UDIA)
Electric Energy Society of Australia (EESA) (Committee)
Engineers Australia (Divisional Committee)
Down to Earth Conference (DTEC)
The Australian Power Institute (API)
CDEGS User Group Australia (Chair)
CIGRE Australia
Institute of Electrical and Electronics Engineers (IEEE)
The Australasian Corrosion Association INC

EARTHING DESIGN & FIELD TESTING

We have substantial experience in ensuring that new electrical infrastructure installed on HV, MV and LV systems will satisfy the specific utility/client requirements as well as comply with Australian and International technical standards and regulations including; AS2067, AS3000, AS7000, AS3007, AS4853, AS3835, ENA EG1, ENA EG0, IEEE 80 and IEEE 81.

APD have the know-how and track record of earthing design and field testing for a wide variety of electrical installations at high, medium and low-voltage, including:

Large zone substations to compact kiosks (220kV – 415V)
Transmission & distribution overhead lines & underground cable
Power stations (thermal units and large-scale PV solar farms)
Electrical reticulation systems in mining plants and land development projects
AC & DC overhead traction system for railway networks
Induced voltages on gas / water pipeline & apparatuses, conveyors, fences, etc.
EPR testing on telecommunication assets (including NBN nodes)

PROJECT PHASE CAPABILITIES

Our capability in design and field testing extends to all phases of a project, including:

SOIL RESISTIVITY MEASUREMENTS

Undertake Dial Before You Dig (DBYD) and prepare site specific test plans
Carry out the soil resistivity measurements
Establish the soil model using CDEGS software package

DETAILED EARTHING DESIGN

Review the network and determine earth fault parameters
Determine the statutory regulations and safety limits
Earth grid conductor sizing
Earthing system arrangement for HV, MV and LV networks
Prepare drawings (earth grid layout and bill of materials)
Develop detailed CDGES model and assess step and touch voltage hazards
Investigate Earth Potential Rise (EPR) for third party infrastructure
Assess step and touch voltage hazards on metallic pipes and apparatuses
Modify the earthing design to address compliance issues and meet safety limits

EPR/LFI HAZARD ASSESSMENT

Investigate transferred (EPR) and Low Frequency Induction (LFI) hazards from neighbouring zone substations, transmission lines and other installations
Assess electrostatic induction & charging on metallic assets
Undertake electromagnetic field studies in compliance with ARPANSA guidelines
Develop Safe Work Method Statement (SWMS) and Safety in Design documents

ON-SITE AUDIT & REPAIR

Visual audit under initial commissioning phase or periodic integrity checks
Check compliance and accuracy of as-built drawing and red-line mark-ups
Check condition of earthing conductors & connections, earth electrodes, bonding conductors, surface layer materials, and perimeter fences & gates
Check the HV/MV/LV earthing arrangements, bonding of metallic pipelines, control / telecom earthing, lightning protection and corrosion protection units
Visual inception of the site and identify 3rd party metallic objects subject to EPR
Address compliance issue and make repairs on site.

FIELD COMPLIANCE TESTING

Earth grid continuity testing
Current injection testing to measure step and touch potential hazards
Fall of potential to measure earth grid resistance
EPR measurement for telecom (nbn) nodes
Injection testing to assess transferred voltages on to third party infrastructure
Step and touch hazard assessment on overhead railway traction installations
Measure local earth grid resistance for lightning protection systems
Post analysis of site measurements and preparation of compliance reports.

LIGHTNING PROTECTION & LIGHTING DESIGN

In addition to detailed earthing design studies, APD offer other engineering services relevant to the earthing system, including lightning protection design as per AS 1768 and lighting design as per and Australian Standard client requirements.

lightning protection

LIGHTNING PROTECTION DESIGN

Lightning protection requirements in compliance with AS1768
Detailed risk assessment and project specific designs
Using SES Shield-3D software to carry out Rolling Sphere or Basic Impulse methods
Powerline earth wire shielding angle and critical back flashover-voltages.

LIGHTING CALCULATIONS & DESIGN

Lighting equipment specification
Appropriate lighting category selection for substations, footpaths, roadways etc.
Orientation and tilt position of lights in various applications
Quantify compliance with glare restrictions
Modelling and LUX level mapping using AGI32 and other software.

INSULATION COORDINATION STUDIES

Lightning overvoltage studies – detailed modelling of using ATP Draw, PSCAD EMTC and other software
Capacitor switching, transformer energisation, load rejection and earth fault over voltage studies and estimation of failure rate
Lightning strike insulation studies and selection of surge arrester
Point-on-wave and circuit breaker TRV studies.

NICHE EARTHING RELATED SERVICES

Incident / Safety Investigations
Railway AC and DC Traction Systems
Earthing design and field testing for large-scale renewable energy systems (large PV solar farms) and battery storage units
Corrosion Assessments and Cathodic Protection Systems
Safe Work Method Statement (SWMS) and Safety in Design documents
Soil Thermal Resistivity – Field and Laboratory Testing.