DIN EN 3475-307:2011-06

The standards of the EN 3475 standard series describe test methods for electrical cables for aircraft use. For an electrical cable, the presence of partial discharges effects at operating voltage may result in a significant reduction of service life. Some insulation materials are more susceptible to such discharge damage than others. Evidence of partial discharges during operation signifies for example: - the insulation thickness is insufficient for the applied voltage; - the quality of the insulation is inadequate possibly due to excessive size of internal cavities or voids; - an overstress is present, resulting in a local reduction of the cable insulation properties. Part 307 defines methods to cover the detection and measurement of partial discharge (corona) under an applied test voltage, including the determination of partial discharges (corona) inception and extinction voltages as the test voltage is raised and lowered, of electrical cables for aircraft use. It shall be used together with EN 3475-100. The following modifications have been made with respect to DIN EN 3475-307:2006-10: a) An explanatory introduction has been incorporated. b) The scope has been extended by the detection, in addition to the measurement, and the partial discharge inception voltage. c) Clause 3 containing the terms partial discharge inception voltage (PDIV) and partial discharge extinction voltage (PDEV) has been incorporated. d) Regarding testing, three different cases of use were named. e) Clause 6 describes the three methods. f) In clause 7, the procedure has been specified according to the expansion of the scope. This standard of the EN 3475 series has been prepared by ASD-STAN, Technical Section Electrics, Avionics, with the participation of German experts of the Aerospace Standards Committee. The European Committee for Standardization (CEN) declared the Aerospace and Defence Industries Association of Europe (ASD-STAN) responsible for the preparation of European standards (EN) for the field of aerospace. The responsible German standardization committee is Working Committee NA 131-04-02 AA "Elektrische Leitungen" ("Electric cables") of the Aerospace Standards Committee at DIN.