Cable fault finder to cut downtime

An intelligent device for locating faults in inaccessible electric and fibre optic cables could dramatically reduce network downtime across a range of industries.

The technology, which is being developed at Strathclyde University, has been designed primarily for use in the power industry, where it will locate faults in multi-conductor electric cables.

But it can also be applied to a large number of other areas where cables are used, such as the oil and gas, telecommunications, railway and aerospace industries.

Unlike current techniques, the technology can identify faults in cable systems with a large number of joints, particularly T-joints, where two cables are connected in a T fashion, said Dr Wah Hoon Siew, senior lecturer in electronic and electrical engineering at Strathclyde University, this week.

Existing fault-detection techniques involve time domain reflectometry, where a signal is sent out and reflected back by the fault, said Siew. ‘Unfortunately, T-joints also cause the signal to be sent back, so you have a range of signals being returned, some from the fault and some from the T-joints.’

An expert is then needed to interpret these signals, but this process is by no means an exact science, he said.

The research team’s device uses a signal-processor to interpret the information received from the time domain reflectometry equipment more quickly and accurately, eliminating the need for expert intervention.

‘It means the location of the fault can be identified very quickly. The sooner a fault can be identified, the faster the network can be brought back into service,’ said Siew.The technology, the brainchild of Siew and his colleague Dr John Soraghan, could be particularly useful in the aerospace industry, as modern aircraft are fitted with large amounts of cabling. And with recent developments in in-flight entertainment, the use of cables within aircraft is expanding, as more airlines fit monitors to the back of each seat, says Siew.

‘Once all these cables are put in position they are generally hidden and become virtually inaccessible, requiring almost a complete retrofit to get to them. If you can identify where the fault is before you start removing seats, it will cut down considerably on the work required.’

The researchers have received £167,000 funding from Scottish Enterprise to develop the technology, and hope to produce a prototype by early 2004.