Redundant input pipe networks in aspirated smoke detectors

摘要

An aspirated detecting system includes a multi-channel aspirated smoke detector with each channel including an air moving element, such as a fan, first and second sets of substantially identical air flow pipes where each set defines a plurality of spaced apart inflow ports. Control circuits activate a first element and then a second element to establish a transport time associated with at least one inflow port in response to the detector sensing a predetermined smoke condition. The control circuits include a storage unit which includes pre-stored timer values which are associated with respective transport times from an associated inflow port. (18-1,-2...n 12 Sampling holes 14 RPN -'R 24 24 -Fans speed indication: 22c 20 f"/ MCH stop MONIT 1 2 RCH stop 22 24a Y 20-1 -2-20-2 C4 CNTRL MCH RCH 9 1 Ck o UNIT 20-3 ASD - 22d 22a 22b ASD,MPN and RPN status after the pipe network installation Sampling holes At Air movement ~~- MPN V RPN X No Air movement 20 , Fans speed indication: MCH normal operation 1 2 RCH stop 22 ASD,MPN and RPN status during normal operations