AC Induction Conductive Suit - A New Way of Protecting Linemen in the Vicinity of Energized Parts

Abstract

Conductive suits are widely used in the industry for live work on transmission lines. This paper covers the use of special conductive suits for AC induction protection on de-energized lines. During de-energized work in the vicinity of live conductors, inductive and capacitive coupling may result in dangerous voltages and currents. Several accidents show that de-energized work has a high-risk level. The main reason is that de-energized parts are supposed to be grounded but line workers often do not have the proper knowledge and safety gear to assess and to protect against sources of induced voltages and currents. A US electric utility in co-operation with the High Voltage Laboratory of the Budapest University of Technology and Economics developed an AC induction suit; a special conductive suit designed to protect line workers against induced voltage and current while working on de-energized systems in the vicinity of energized lines. The range of induced voltage and current was analyzed based on preliminary calculations, and field measurements. The design of the special protective suit was based on these physical values. Several laboratory tests were performed to validate the results and to inspect prototypes at extreme voltages and currents. The aim of the developers is to increase the overall level of safety during vicinity work in transmission corridors with high AC induction and to greatly reduce accidents. Requirements for induction suits and test methods to prove protective capabilities will be standardized in the future. Based on the positive results of the prototype tests, a new product was introduced in the US market. The suits are currently being tested by the electric utility to gather experience, develop field procedures, and to effectively reduce the risk level, treating safety always as priority.