Reducing failure in underground cables

By Y Wang, EA Technology Group

 

Published in:

Electricity+Control, October 2013 (pages 16 – 18)

Enquiries: Email ying.wang@eatechnology.com.au;

john.hartford@eatechnology.com.

Tel. 011 432 6958 or email fred@ipiholdings.co.za

 

The full article on Reducing failure in underground cables can be downloaded in PDF format.

 

The process of capturing partial discharge (PD) data with the Cable Data Collector described in this article is quick and simple. The technique involves energising the cables at very low frequencies. This allows the measurement of cable length by time of flight measurements, as well as identifying any PD activity in the reflected waveforms.

Specific software has been developed to analyse the results to produce a comprehensive report on the health of the cable and identify any areas that may require further investigation or repair. Both the online and offline testing techniques offer many benefits compared with extensive and costly physical excavations, to inspect the condition cables visually. In addition to identifying the presence of potentially failure-causing PD activity, they are equally valuable at assuring operators when cables are functioning without PD being present, and thus at low risk of failure.

 

Take note

  • Cables are reliable and offer a secure supply option.
  • Cables must be managed over their lifecycle.
  • Monitoring devices for cables offer a reliable way of condition management.