About Cable Fault Locators
Cable fault locators are integral in the maintenance of underground power distribution networks. The efficient and uninterrupted flow of electricity is crucial. Just like any other infrastructure, underground cables can encounter faults and disruptions, leading to power outages and inconveniences.
Underground cables are susceptible to various types of faults, including insulation failures, physical damage, water ingress, and even aging. Locating and rectifying these faults can be a challenging and time-consuming due to the concealed nature of the cables. Traditional methods of locating cable faults often involve extensive excavation - a costly and disruptive task! Advances in underground cable fault locators have revolutionised this process.
A cable fault is a failure involving the most vital component inside of a power cable: the bulk insulation between the centre conductor and neutral. This will inevitably cause unexpected and expensive outages, negatively impacting key performance indicators!
Utility company fault locating crews and service contractors carry out the critical work of locating these faults as quickly and as safely as possible.
Due to the different nature of the various different types of faults, cable fault location is a troubleshooting process - methods and technologies applicable to a certain type of fault might not be useful for other faults. Therefore, more than one type of cable fault locator is required. Having all the required cable fault locators enables the engineers out in the field to react appropriately to any fault.
The modern fault locating approach involves three steps: using a surge wave generator with a multi-stage capacitor for cap discharge (surging, thumping), a high voltage DC source, a set of filters and couplers, and a radar (time domain reflectometer, TDR).
The 3 Steps Of Cable Fault Location
The first step when trying to find a fault is to identify the type of fault; this will narrow down the choice of viable methods for the subsequent steps.
The second step is to carryout prelocation methods so an approximate distance to the fault can be determined.
The third step is based on the previous prelocation results. The exact position of the fault must be determined by pinpointing using pinpointing devices.
Employing various Cable fault locators/techniques help achieve the above 3 steps:
Time Domain Reflectometry (TDR): TDR is a widely used technology in cable fault locators. It sends a low-energy electrical pulse into the cable and measures the time it takes for the pulse to return after encountering a fault. By analysing the time delay and pulse reflection, the device can precisely determine the distance to the fault.
Acoustic Methods: Some fault locators use acoustic techniques to detect cable faults. These devices send acoustic signals into the cable, and the reflections produced by the fault can be analysed to identify the fault's location.
Surge Generators: Surge generators create high-voltage pulses to pinpoint insulation faults. When the pulse encounters the fault, it produces a surge, which can be detected and used to locate the fault.
Fault Sniffers: Most cable faults result in burns of the cable sheath. The resulting gases are sucked in and detected by the vacuum technology. The evaluation of the data is done in real-time and gives you a graphical representation of the burning gas concentration. The cable fault is located at the point of highest measured gas concentration.
Benefits of Underground Cable Fault Locators
The use of Underground Cable Fault Locators provides several advantages:
Time and Cost Savings: The most significant advantage of these devices is the substantial time and cost savings they offer. Locating faults without the need for extensive excavation reduces downtime, labour, and material costs.
Minimised Disruption: With pinpoint accuracy, Cable fault locators minimise disruption to the surrounding area. This is particularly important in urban environments, where digging up streets can be highly disruptive.
Improved Safety: Underground cable fault locators enhance safety by reducing the need for workers to dig trenches or engage in potentially hazardous activities. This lowers the risk of accidents and injuries.
Faster Restoration of Power: By swiftly identifying and repairing cable faults, underground cable fault locators expedite the restoration of power, improving the overall reliability of the electrical grid.
Environmental Benefits: The reduction in excavation and digging helps preserve the environment, preventing damage to landscapes and ecosystems. Cable fault locators have revolutionised this process, enabling quick and accurate identification of faults in underground power cables, saving time and resources while minimising disruptions.
If you have any questions contact our friendly team today - experts are here to advise on the full range of cable fault locators.