A SMOKE DETECTOR CONTROL UNIT - SDCU FOR AIRBUS A340 ALSO COMMON TO AIRBUS A330 CIVIL AIRCRAFT. THE SDCU HAS THE FOLLOWING FUNCTIONS - TO MONITOR AND PROCESS THE SIGNALS OF THE SMOKE DETECTORS FOR THE AVIONICS SMOKE DETECTION SYSTEM, LDCC SMOKE-DETECTION SYSTEM, LAVATORY SMOKE-DETECTION SYSTEM. TO MONITOR THE FIRE EXTINGUISHING SYSTEM. TO SUPPLY THE DETECTORS WITH A CONTROLLED VOLTAGE THROUGH A TWO WIRE SAFETY BUS SYSTEM. IT IS PROTECTED AGAINST ONE SHORT CIRCUIT OR ONE OPEN CIRCUIT BETWEEN TWO SMOKE DETECTORS ON EACH BUS LOOP, WITHOUT THE LOSS OF THE DETECTOR FUNCTION. THIS UNIT HAS NO SOUND OR VISUAL SIGNAL, THE UNIT JUST PASSES THE ELECTRICAL SIGNAL TO OTHER APPARATUS WITHIN THE SYSTEM TO PROVIDE THE WARNING. THE SYSTEM DOES NOT CONTAIN ANY RADIOACTIVE SUBSTANCE.

CLASSIFICATION HAS BEEN DETERMINED IN ACCORDANCE WITH THE FOLLOWING :- GENERAL INTERPRETATIVE RULES (GIRs) GIR 1 HAS BEEN USED TO CLASSIFY THIS PRODUCT BY THE TERMS OF HEADING 8537 - BOARDS, PANELS, CONSOLES, DESKS, CABINETS AND OTHER BASES, EQUIPPED WITH TWO OR MORE APPARATUS OF HEADING 8535 OR 8536, FOR ELECTRIC CONTROL OR THE DISTRIBUTION OF ELECTRICITY, INCLUDING THOSE INCORPORATING INSTRUMENTS OR APPARATUS OF CHAPTER 90, AND NUMERICAL CONTROL APPARATUS, OTHER THAN SWITCHING APPARATUS OF HEADING 8517 GIR 6 HAS BEEN USED TO CLASSIFY THE GOODS TO SUBHEADING LEVEL 853710 :- FOR A VOLTAGE NOT EXCEEDING 1000 VOLTS. CN CODE - 85371098 - OTHER THAN ELSEWHERE SPECIFIED WITHIN THIS HEADING TARIC CODE - 8537109810 - FOR USE IN CERTAIN TYPES OF AIRCRAFT ALSO CLASSIFIED IN ACCORDANCE WITH THE SCOPE OF HSEN 8537.