Non-contact voltage detector could

reduce electrical deaths and injuries

In a recent incident, a worker was electrocuted when he received an electric shock from a backfeed source. The high-voltage line worker was commissioning a 25 kV distribution system. Believing that all underground cables had been de-energized, he did not test to ensure that there were no live power sources before he started work. He was electrocuted when he came in contact with the electrical switchgear.

Other workers have been injured when they came in contact with energized low-voltage or high-voltage equipment.

Non-contact voltage detector

A simple voltage tester can warn workers that the electrical equipment is live, without making a physical connection. This device can detect the electric field, which is present whenever there is voltage even if no current is flowing. The tester gives visual and audible signals from up to a metre away. These pocket-sized testers are available from several suppliers.

Workers must still follow procedures for de-energizing and lockout, where required. The voltage detector provides an additional check to verify that the equipment has been completely de-energized.