Underground Cable Fault Detection Across Geelong & Victoria
Find the fault before you dig — saving time, cost, and unnecessary excavation.
A failed underground cable is a disruption — to power, to communications, to irrigation, to operations. The question isn’t whether to fix it. It’s how much excavation you’ll need to find it first.
Geoscan uses advanced underground cable fault detection equipment to pinpoint the exact location of a fault along any buried cable — to within centimetres, at depth, without digging. Once we’ve located the fault, your electrical or communications contractor knows precisely where to excavate. No guesswork, no trench runs, no wasted time.
Projects Completed
Years Experience
DBYD Certified
Fully Insured
The Problem with Digging Before You Know Where the Fault Is
When an underground cable fails, the temptation is to start digging along its route until the fault is found. For a short cable run this might be manageable. For any significant length — and particularly for HV electrical, Telstra infrastructure, or large irrigation networks — open trenching without a known fault location is expensive, disruptive, and completely avoidable.
Cable fault detection uses electrical test methods to measure the precise distance from a test point to the fault location — then GPR and ground marking to confirm the exact surface position for excavation. The result is a pinpoint target for your excavation contractor, not a guess.
Without fault detection
Open trench excavation along the cable route — potentially hundreds of metres of digging to find a fault that may span centimetres. High cost, major site disruption, slow restoration.
With Geoscan fault detection
Fault located to within centimetres. Excavation contractor opens one targeted pit or trench section. Repair completed in hours rather than days. Costs minimised.
For live electrical systems
An unlocated HV or LV cable fault is a live safety hazard. Digging without knowing the fault location risks striking a compromised cable under load — a serious incident risk.
For communications and telco
A Telstra or communications cable fault takes a service offline. Every hour without detection is another hour of downtime for the businesses or infrastructure depending on it.
Underground Cable Systems Geoscan Can Test
Geoscan’s cable fault detection equipment covers the full range of underground cable types used in commercial, industrial, agricultural, and telecommunications infrastructure across Victoria.
Telstra & Communications Cables
Copper telephone and communications cable faults — locating breaks, shorts, and earth faults along Telstra-managed or privately owned comms infrastructure.
Data & Communications Conduit Cables
Data, network, and communications cable faults in conduit systems — relevant for commercial premises, campus networks, and building infrastructure.
Low Voltage (LV) Electrical Cables
Underground LV supply faults serving residential, commercial, and small industrial properties — earth faults, open circuits, and partial faults all detectable.
High Voltage (HV) Electrical Cables
Underground HV cable fault location for distribution networks, substation feeders, and industrial supply cables — precise fault location before any planned outage or excavation.
Irrigation Cable Systems
Control and power cable faults in agricultural and turf irrigation systems — locating faults in solenoid wiring, pump control cables, and multi-core irrigation control systems across farms, golf courses, and sports facilities.
Combined Cable & Utility Locating
Need to locate a cable fault and map surrounding utilities in the same visit? Geoscan’s team can combine fault detection with electromagnetic utility locating — one mobilisation, one invoice.
How Underground Cable Fault Detection Works
Contact Us & Brief the Fault
Tell us the cable type, the approximate route length, what the cable supplies, and what symptoms you’re seeing — whether it’s a complete failure, intermittent fault, or partial breakdown under load. The more information you can provide, the more efficiently we can deploy the right test method. We’ll confirm mobilisation and provide a fast quote.
On-Site Testing & Fault Location
Geoscan’s technician connects to the cable at the nearest accessible test point and applies the appropriate electrical test method for the fault type — time domain reflectometry (TDR), Murray loop test, or impulse/surge testing depending on the cable system and fault signature. The test measures the distance from the test point to the fault with precision, narrowing the fault location to a specific span of cable. GPR is then used where required to confirm the cable route and provide the exact surface position for excavation marking.
Fault Marked — Ready for Repair
The fault location is marked on the ground surface, giving your electrical contractor, telco technician, or civil crew an exact point to excavate. We provide a written report confirming the fault type, test method used, distance measurement, and the surface location — suitable for your records, contractor briefing, or insurance documentation.
Who Calls Geoscan for Cable Fault Detection
Underground cable faults don’t follow a schedule — and neither do we. Geoscan works with clients who need a cable fault found quickly and accurately, the first time.
Electricians & Electrical Contractors
LV and HV cable fault location before excavation — identifying the fault point so your crew can open one pit rather than a trench run.
Telecommunications Contractors
Telstra and comms cable fault location for copper pairs, data cables, and multi-conductor systems — minimising service disruption and excavation scope.
Irrigation & Agricultural Contractors
Solenoid, pump, and control cable faults on farm, turf, and recreational irrigation systems — quickly identifying the fault before the irrigation season is impacted.
Facilities & Asset Managers
Cable fault detection for commercial, industrial, and institutional buildings — locating faults in supply cables, campus networks, and buried electrical infrastructure.
Councils & Infrastructure Owners
Street lighting, traffic signal, and public infrastructure cable fault location — supporting councils across Geelong and Victoria to maintain public assets with minimum disruption.
Civil Contractors & Project Managers
Pre-excavation cable fault clearance and live cable identification before any ground-breaking works on sites with unknown or complex underground electrical infrastructure.
Why Industry Professionals Choose Geoscan for Cable Fault Detection
Precise Fault Location — Not an Estimate
We use TDR, Murray loop, and surge testing methods to locate faults with precision — not a guess, not a zone, but a specific point on the cable. Your excavation contractor gets an exact target.
Minimise Excavation — Reduce Cost
Targeted fault location means targeted excavation. Instead of opening a trench run along the full cable route, your crew opens one pit at the fault point. Less excavation, less reinstatement, lower cost.
Full Range of Cable Types
Telstra copper, LV and HV electrical, data and communications, and irrigation control cables — Geoscan’s fault detection capability covers the full range of underground cable systems used across Victoria.
Combined Fault Detection & Utility Locating
Need to locate the fault and map surrounding utilities in the same visit? Geoscan can combine cable fault detection with electromagnetic utility locating and GPR — one team, one mobilisation, complete subsurface picture.
Documented Report for Your Records
Every fault location job includes a written report — fault type, test method, measured distance, and surface location. Suitable for contractor briefing, insurance claims, asset management records, and regulatory documentation.
28+ Years Experience, Geelong-Based
Based in Geelong with over 28 years of underground services experience — we understand local infrastructure, respond fast, and mobilise across Victoria with minimal lead time.
Frequently Asked Questions
What is underground cable fault detection and how does it work?
Underground cable fault detection is the process of locating the precise position of a fault along a buried cable — whether that’s a break in the conductor, an insulation failure, a short to earth, or a partial breakdown. Geoscan uses electrical test methods including time domain reflectometry (TDR), Murray loop testing, and surge/impulse testing to measure the distance from a test point to the fault with precision. Once the fault distance is established, the cable route is traced and the fault position is marked on the ground surface for targeted excavation.
What types of cable faults can you locate?
Geoscan can locate the most common types of underground cable faults, including: open circuit faults (broken conductor), short circuit faults (conductors touching), earth faults (insulation breakdown causing leakage to ground), and high-resistance or partial faults (degraded insulation that may still allow some current flow). The appropriate test method depends on the fault type and the cable system — we advise on the right approach once we understand the symptom.
What cable types do you test?
Geoscan tests faults in Telstra and copper communications cables, data and network cables, low voltage (LV) electrical supply cables, high voltage (HV) distribution cables, and irrigation control and solenoid cables. If you’re unsure whether your cable type is within scope, contact us and we’ll confirm.
How accurate is the fault location?
Cable fault location accuracy depends on the cable type, length, fault type, and test method used. Under good test conditions, TDR can locate faults to within 1–2% of the cable length — meaning on a 100-metre cable, the fault would be located to within 1–2 metres, which is then refined to a specific surface position using GPR and cable tracing. For shorter runs and simpler fault types, precision is typically higher. Geoscan will advise on expected accuracy for your specific cable system at the quoting stage.
Do you need access to both ends of the cable?
Not always. Many fault test methods — particularly TDR — can be performed from a single access point, sending a signal along the cable and measuring the reflection. Murray loop testing and some other methods require a loop connection, which may need access at the far end. Geoscan will advise on access requirements when you describe the cable system and the fault symptoms.
Can you locate a fault in a live cable?
Cable fault testing is generally performed on de-energised cables for safety — particularly for LV and HV electrical systems. For communications and irrigation cables, the test requirements vary. Geoscan will advise on de-energisation requirements and coordinate with your electrical contractor or network authority where necessary. We never apply test equipment to a live electrical cable.
What areas do you service?
Geoscan is based in Geelong and provides underground cable fault detection services across Victoria, including greater Melbourne, the Surf Coast, Bellarine Peninsula, Western Victoria, and regional areas statewide. Contact us to discuss your project location and we’ll confirm availability and mobilisation.
Cable Fault Found Fast — Anywhere in Victoria.
Whether it’s a failed LV supply cable, a Telstra fault taking a business offline, or an irrigation control cable that’s stopped a farm’s season — Geoscan’s team can locate the fault precisely and get your contractor to the right spot the first time. Get in touch for a fast, no-obligation quote.
Monday – Friday | 7:30 AM – 4:30 PM