DIN EN 3773-004:2014-12

Standard series EN 3773 specifies the characteristics of single-pole circuit breakers, temperature compensated with a rated current from 1 A to 25 A, used in aircraft on-board circuits. The new edition of Part 004 specifies the characteristics of single-pole circuit breakers with UNC thread terminals for use in aircraft on-board circuits at a temperature between -55 °C and 125 °C and at an altitude of 22 000 m max. These circuit breakers are operated by a push-pull type single push button (actuator), with delayed action "trip-free" tripping. They will continue to function up to the short-circuit current. Compared to the previous edition of DIN EN 3773-004:1999-08, the following modifications have been made: a) in the scope, the reference for use in aircraft with electrical supplies in accordance with EN 2282 has been deleted; b) the normative references have been changed; c) the structure and contents of the standard have been changed and enlarged fundamentally, instead of the former Clause 4 Required characteristics, Clause 4 for Dimensions and mass and Clause 5 Characteristics have been added, the clauses regarding the data of connection elements have been deleted with reference to EN 6113; d) in addition to the numerous statements regarding materials, surface treatment, mechanical characteristics and environment characteristics, with 5.4 a clause with various tables with requirements for the electrical characteristics has been introduced; e) for the identity block in Clause 6, Table 8 regarding the rated current code in Clause 7 and Clause 8 with delivery codes for the equipment have been introduced; f) in Clause 9 extended requirements for the marking and in Clause 10 a statement regarding the technical delivery conditions have been added. The standards of the EN 3773 series are 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 131-04-05 AA "Schalter, Relais und Schutzgeräte" ("Switches, relays and protection devices") at the DIN Standards Committee Aerospace.