Real time multi-channel gas leakage monitoring system using CPLD chip

A multi-channel gas leakage monitoring system was designed and fabricated b y using complex programmable logic device (CPLD) for monitoring and control ling the leakage of natural gas from the natural gas supplying pipeline und er the ground. A planar structure gas sensor was attached under safeguard s teel plates of natural gas supplying pipeline, and the local monitoring sys tem which networked with a number of gas sensors received the signals from the attached gas sensors. The monitoring system was implemented by using CP LD chip to reduce the developing time for the system and the system size. T he time sharing multi-channel system received the input signals from indivi dual gas sensors at divided periodic times and signal-processed sequentiall y. The fabricated system could monitor the local area of natural gas pipeli ne with the miniature monitoring system. (C) 2001 Elsevier Science B.V. All rights reserved.