A Day in the Life of Sparks #2: Underground Cable Fault + Repair
UNDERGROUND CABLE faults are generally the result of damage caused to a cable either during the installation or from excavation by workmen or mechanical diggers. Damage caused by a digger was the case in a recent job to trace a mains supply cable fault that had resulted in the loss of the electricity supply to a customer’s property in Callosa.
As was discovered, ironically, it was Iberdrola who had damaged the cable some years earlier when digging out a foundation for an electricity pylon that supplied electricity to the home. The fault was buried in the concrete of the foundation, and as is normally the case in these instances, the repair was totally inadequate. It became only a matter of time before it broke down.
Underground cable repairs should be treated very differently to those cable repairs which are carried out above ground. Special materials must be used if the repair is to withstand water ingress being buried underground.
Using a cable jointing kit which comes with a plastic mould and is fitted around the joint then filled with resin is the correct method for repairing underground cables (see right photo). Tapped joints and connector blocks are not suitable.
Special attention must also be given to the cable trench, type of cable and duct if you want to avoid a repeat of the exercise a few years down the line.
More photos click here