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Professional Electrical Services

Underground electrical

fault locating services

Finding the exact location of a cable fault requires special techniques. We can pinpoint a cable fault under ground, paving or concrete. Fill in your contact details on the form below and we’ll call you back within 2 minutes!


electrical services

How Do I Locate An Underground Cable Fault? 


By using a high voltage surge generator (thumper), you can pinpoint an underground fault exactly where it is.


This special technique involves a cable thumper which is essentially a portable high voltage surge generator. It injects a high voltage DC surge of approximately 25 kV into the faulty cable. By supplying a high enough voltage to the faulty cable, the open-circuit breaks down. It creates a high-current arc which makes a distinct thumping sound exactly where the fault is located.


Finding an underground cable fault using this thumper method requires the setup of a thumper to thump repeatedly while an electrician walks along the cable route to hear the thumping sound. As the DC voltage supply increases, the thump becomes louder.

Why Use The Cable Thumping Method? 


The cable thumping method works well for fairly short cables. It can locate open circuit faults with extreme accuracy. With longer cables, it becomes less practical to use the cable thumping method as it would be both cumbersome and time-consuming to walk along a cable that runs kilometers long to listen out for the distinct thump.


 We can assist with cable fault finding. HJJ Electrical has the expertise and equipment to do it correctly and comprehensively. Trust our team to pinpoint your cable fault under ground, paving or concrete in no time!

Got An Underground Cable Fault Request? 

Fill in your contact details on the form below and someone from our team will give you a call back.