CS-VLA 1357 Circuit protective devices

• ED Decision 2003/18/RM found in: CS-VLA Amdt 1 - Very Light Aeroplanes (Mar 2009)

CS-VLA 1357 Circuit protective devices ED Decision 2003/18/RM (a) Protective devices, such as fuses or circuit breakers, must be installed in all electrical circuits other than - (1) The main circuit of starter motors; and (2) Circuits in which no hazard is presented by their omission. (b) A protective device for a circuit essential to flight safety may not be used to protect any other circuit. (c) Each resettable circuit protective device (‘trip free’ device in which the tripping mechanism cannot be overridden by the operating control) must be designed so that - (1) A manual operation is required to restore service after tripping; and (2) If an overload or circuit fault exists, the device will open the circuit regardless of the position of the operating control. (d) If the ability to reset a circuit breaker or replace a fuse is essential to safety in flight, that circuit breaker or fuse must be so located and identified that it can be readily reset or replaced in flight. (e) If fuses are used, there must be one spare of each rating, or 50% spare fuses of each rating, whichever is greater.