PowerEarth has been developing earthing test methods and, together with our partners, specialist test instrumentation for over 20 years. Our testing capability spans the full lifecycle of an earthing system — from pre-design soil resistivity surveys through to compliance verification, routine audits and commissioning of complex electrical installations.
All testing is conducted by experienced engineers using PowerEarth-owned equipment, stored at our offices around Australia, in accordance with AS 2067, AS/NZS 3000, ENA EG-0, IEEE 81 and other relevant Australian and international standards. Our test results provide the quantified evidence you need for design inputs, compliance certification, condition assessment and investment decision-making.
Our Testing Services
Soil Resistivity Surveys
Accurate soil resistivity data is the foundation of every earthing design. PowerEarth conducts Wenner four-pin soil resistivity surveys across your site, measuring the electrical properties of the soil at multiple depths and locations. Results are modelled using CDEGS RESAP to develop multi-layer soil resistivity profiles that inform earthing system design, crushed rock resistivity assessments and earth electrode specification. Surveys are conducted in accordance with IEEE 81 and applicable network operator requirements.
Current Injection Testing
Current injection testing is the definitive method for verifying the performance of an installed earthing system. PowerEarth injects a known off-frequency test current into the earthing system and measures the resulting earth potential rise (EPR), current distribution through earth conductors and overhead earth wires, and step and touch voltages at accessible locations. Our injection testing verifies that the earthing system performs as designed, identifies any deficiencies requiring remediation and provides measured data for compliance reporting under AS 2067 and ENA EG-0.
Fall of Potential Testing
Fall of potential testing measures the impedance of the earthing system by injecting a test current and measuring the voltage at increasing distances from the earth electrode. This test confirms that the earth resistance meets design targets and regulatory requirements. PowerEarth uses calibrated test equipment and proven methodologies to deliver accurate results, even on large or complex earthing systems where test lead routing and electrode placement require careful planning.
Continuity Testing
Continuity testing verifies that all components of the earthing system — earth conductors, bonds, connections to equipment and electrode systems — are physically connected and provide a low-impedance current path. Our engineers test every critical connection in the earthing network, identifying any open circuits, high-resistance joints or missing bonds that could compromise system performance during a fault. Continuity testing is a standard component of both commissioning and routine compliance audits.
Interference Voltage Testing
For sites near DC traction systems or other DC power sources, PowerEarth conducts interference voltage testing to assess the risk of stray current corrosion on buried metallic infrastructure. These tests measure the voltage between the structure and a reference electrode under operational conditions, identifying locations where stray current is entering or leaving the structure and quantifying the corrosion risk. Results inform the design of mitigation measures including drainage bonds, insulating joints and cathodic protection coordination.
AC Electric and Magnetic Field Measurements
PowerEarth measures AC electric and magnetic field levels at substations, transmission line corridors and other high voltage installations to assess compliance with exposure limits and evaluate electromagnetic interference risks to sensitive equipment. Measurements are conducted in accordance with relevant Australian guidelines and can support environmental impact assessments, workplace exposure monitoring and equipment immunity evaluations.
EMI Testing for DC Traction Systems
DC traction systems can generate electromagnetic interference that affects signalling, communications and control systems. PowerEarth’s EMI testing for rail and transport projects measures interference levels across relevant frequency ranges and assesses compliance with signalling immunity requirements, providing the data needed to design effective shielding and separation strategies.
Crushed Rock and Loose Aggregate Resistivity Testing
Crushed rock is widely used as an earthing surface treatment in substations, BESS yards and other high voltage installations to manage step and touch voltage risks. AS 2067:2016 specifies a minimum resistivity of 3,000 Ω.m for this layer, yet PowerEarth’s testing experience shows that many existing installations fall well below this value, often measuring between 1,000 and 1,500 Ω.m, due to smaller particle sizes, contamination with fines or organic matter.
PowerEarth provides wet and dry resistivity testing of crushed rock and loose aggregate samples, aligned with AS 2067:2016 and ENA EG-0. We require only a 20-litre sample, making the process straightforward: request a quote, ship us your material, and we deliver clear, standards-referenced results.
Learn more about our crushed rock and loose aggregate resistivity testing service →
Earthing System Audits
PowerEarth conducts audits of existing earthing systems against AS 2067, AS/NZS 3000 and network operator standards. Our audits assess the physical condition of the earthing system, review documentation and design basis, test system performance and identify any non-compliances or areas requiring remediation. Audit reports provide practical recommendations with prioritised actions, supporting asset managers in maintaining safe and compliant earthing systems across their portfolios.
Commissioning Services
PowerEarth provides tailored commissioning services to verify that newly installed or modified electrical systems meet design intent and industry standards. Our commissioning scope extends beyond earthing to cover complex electrical network designs, electrical system design verification, energy storage systems and Smart Grid-based installations — all under stringent quality assurance procedures.
We develop commissioning test procedures, witness factory and site acceptance testing, verify system performance against design parameters and provide commissioning completion reports. Our engineers coordinate closely with construction teams and asset owners to ensure that commissioning activities are completed safely, efficiently and with minimal disruption to operations.
When You Need Testing
PowerEarth’s testing and audit services are required at many points in the lifecycle of an electrical asset:
- Pre-design: Soil resistivity surveys to provide design inputs for new earthing systems
- Commissioning: Current injection testing, continuity verification and fall of potential testing to confirm that installed earthing systems meet design and compliance requirements
- Routine compliance: Periodic testing and audits to verify ongoing compliance with AS 2067, ENA EG-0 and network operator standards
- Condition assessment: Testing to evaluate the condition of ageing earthing systems and inform maintenance or replacement decisions
- Post-incident: Testing and investigation after equipment failures, protection operations or safety incidents involving the earthing system
- Change management: Testing to verify earthing system performance after modifications, extensions or changes to fault levels
Frequently Asked Questions
What is current injection testing and when is it needed?
Current injection testing involves injecting a controlled off-frequency test current into an earthing system and measuring the resulting voltages and current distribution. It is the most accurate method for verifying earthing system performance in the field. Current injection testing is typically required during commissioning of new high voltage substations, after modifications to existing earthing systems, and as part of periodic compliance verification under AS 2067 and ENA EG-0.
How often should earthing systems be tested?
Testing frequency depends on the asset type, risk profile and applicable standards. Network operators typically require earthing compliance testing at intervals of five to ten years for substations and high voltage installations. More frequent testing may be required for assets in corrosive environments, areas with changing soil conditions, or installations that have undergone modifications. PowerEarth can advise on an appropriate testing schedule based on your specific asset portfolio and regulatory requirements.
What is the difference between an earthing audit and earthing testing?
An earthing audit is a comprehensive review that assesses the physical condition, documentation, design basis and compliance status of an earthing system. It includes visual inspection, document review and may include selective testing. Earthing testing refers specifically to the electrical measurements — such as soil resistivity, earth resistance, continuity and current injection testing — that quantify the system’s performance. A thorough audit typically includes both elements, but testing can also be conducted as a standalone service for commissioning or routine compliance purposes.
What equipment does PowerEarth use for earthing testing?
PowerEarth owns and maintains a comprehensive fleet of specialist earthing test equipment, stored at our offices around Australia for rapid deployment. This includes high-power current injection test sets for off-frequency EPR testing, Wenner four-pin soil resistivity test equipment, fall of potential test sets, micro-ohm meters for continuity testing, and interference voltage measurement equipment. All instruments are regularly calibrated and maintained to ensure accurate, reliable results.
Can you test earthing systems on live sites?
Yes. Many of our testing methods — including soil resistivity surveys, continuity testing and interference voltage measurements — can be conducted while the site remains operational. Current injection testing typically requires coordination with the asset owner and may require specific switching arrangements to ensure safety, but does not necessarily require a full shutdown. PowerEarth works with your operations team to plan testing activities that minimise disruption while maintaining safety.
What standards apply to earthing testing in Australia?
The key standards include AS 2067 (Substations and High Voltage Installations) which specifies earthing testing requirements for HV installations, ENA EG-0 (Power System Earthing Guide) which provides risk-based guidance on test methods and acceptance criteria, AS/NZS 3000 (Wiring Rules) for LV earthing testing, and IEEE 81 (Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials) which provides detailed test methodologies. Network operators may also have their own specific testing standards and requirements.
Talk to Our Testing Team
Whether you need a soil resistivity survey for a new project, current injection testing for commissioning, a compliance audit across your asset portfolio, or specialist EMI testing for a rail corridor, PowerEarth has the equipment, methodology and 20 years of testing experience to deliver. We work efficiently to minimise disruption and provide clear, practical reports that support your compliance and asset management decisions.
Contact us today to discuss your testing requirements, or call us on 1300 POWEREARTH.