Accidental electrocution

Sarnoff Corporation has developed a mobile system that can check street-level objects for “stray voltage” leaks that can injure and kill pedestrians in urban centres.


Stray voltage is caused by electricity leaking from the electrical distribution grid into exposed objects, where it can pose a serious threat of shock to anyone who comes in contact with it.


The mobile system, the SVD1000, scans its surroundings while being towed on a trailer behind a utility vehicle at speeds of up to 20 miles/hour. The SVD1000 can detect potential shock hazards at distances of up to 25 feet, depending on operating conditions.


“The number of stray voltage problems increases as the electrical grid in an area grows more complex, and as the infrastructure ages,” said Christos Polyzois, Senior Director, Commercial Systems at Sarnoff. “Damaged connections and cables can electrify street-level structures with lethal levels of voltage.


“In addition to detecting these dangers, the SVD1000 has been able to detect objects electrified with as little as 5 volts. This high sensitivity allows the SVD1000 to help identify minor problems before they become more dangerous.”


Until now detection of these hazards required the manual inspection of each and every potentially electrified object within a city. In large cities this is a difficult task to complete even once a year. To compound the problem, an annual checkup is often insufficient, as new hazards can materialize more frequently.


The Sarnoff SVD1000 enables electric companies to complete rapid inspections of an entire city several times a year, even monthly or weekly when deploying multiple SVD1000’s. “For utilities looking to establish and continually maintain a high level of safety in their infrastructure, this is a necessary tool,” said Polyzois.


The system consists of a proprietary detector mounted in a non-conductive housing, plus specialized electronics and software. It monitors electromagnetic fields as it passes by street-level structures, and alerts its operator to any potential problems it detects so they may be repaired.