How cable alarms are being used to thwart criminals

Cable theft has plagued South African industry for decades, and is an issue that requires much more than technology to solve. Despite this, Ian Loudon, international sales and marketing manager at Omniflex, explains how advances in remote monitoring are giving businesses a fighting chance.

It’s Wednesday night in Amanzimtoti on the south coast of KwaZulu-Natal, South Africa, and two members of the private security firm hired by Telkom, a major telecoms provider, head out to investigate an alarmthat’s been triggered. On arrival, they discover that one of the cables in the cabinet is cut and telephone handsets are strewn on the grass. It seems criminals have broken into the panel and cut the wire to make illegal international telephone calls as part of an elaborate scam.

The team is still investigating when one of the security officers receives a phone call alerting them of an alarm that’s been triggered just down the road. In the pitch black, they use torches to explore the bushes off the main road, and a few minutes into the search, a security guard finds the problem — 500 metres of copper wire has been ripped out.

Had the thieves managed to get away with the cable, they would have melted down the cable to remove the plastic insulation and sold it to a scrapyard for around 900 Rand, or about $50 US dollars. For the company who has been a victim of this theft, it will cost ten times that to replace the cable and repair the critical infrastructure.

This story, which was broadcast in a special assignment by the SABC TV network in late October 2001, highlights just how prevalent and damaging cable theft is. Two decades on, the South African Chamber of Commerce and Industry estimates that cable theft costs the economy between R5–7 billion a year. It mostly involves the theft of copper cable from mines, pipelines, railways, telecoms and electrical utilities.

Security measures

So, what measures have companies used to tackle the problem? For most companies it means investing in security; physical fences and barriers, and visible patrols and guards. Many sites combine this with CCTV and even offer financial incentives for information about cable theft.

However, for many sites these measures are prohibitive. In the mining sector, for example, sites can span large geographic areas over dozens of square kilometres or more, and the cost of installing fencing and employing patrols and CCTV operators can quickly rack up. A fact that the criminals know all too well.

In mining areas, the sparse security means that thieves can drive a truck right up to the electrical substation or control panel, cut the cable and attach it to the vehicle’s tow-bar and rip the cable right out of the ground. The result is an instant loss of power to the mine’s operations, killing everything from pumps and ventilation fans to lighting and conveyors.

Cable alarms

One popular option in recent years has been the use of alarms that detect a system power failure. These are electrical devices that alert the mine owner when the power goes out — a potential sign that the cable has been cut. However, the problem with these systems is that they fail to distinguish between a genuine power outage and a criminal who has cut the wire.

Because South Africa uses load shedding, or rolling blackouts, to manage electricity supply and demand — and the schedules for these planned outages are made public — thieves time their robberies down to the minute. They wait until the power goes out and then strike, stealing the cable and making their getaway before the power comes back on. The typical alarms used in these situations register the power cut as a false-positive, meaning that the mine owner doesn’t realise the cable has been stolen until much later.

As a remote monitoring specialist, Omniflex understood this problem better than most and recently developed the Silent Sentry. This is a GSM-based, battery powered remote terminal unit (RTU) that monitors to see whether the cable circuit is open or closed, unlike other alarm systems that simply look for the presence or absence of power. This means that in the event of a power outage, the Silent Sentry detects whether a cable has been cut, continues to run on battery power, and sends SMS alerts to the owner.

However, this only treats the symptom, not the cause. The criminals on the ground are a small part of a much wider problem that requires enforcement across the scrap-metal supply chain. There needs to be a wider effort across industry, law enforcement and government to eliminate the problem. In the meanwhile, you can give your security a fighting chance by using the right alarms to tackle cable theft.

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