USING ELECTRICAL RESISTANCE FOR LEVEL MEASUREMENT AND CONTROL

摘要

Operating principles of unique distributed resistance sensors for combined level and temperature measurement are set forth, and use of discrete and adjustable thresholds for alarm and control operation is presented. Two areas of field application are cited as examples. First is land-based tank farm gauging, such as for airline fuel management, including remote inventory monitoring, reorder alarming, tank loading control and fill alarming, overall tank farm surveillance and lass prevention. Such properties as tank-top mounting, absence of moving parts, combined level and temperature sensing, and low maintenance are shown to be provided for such tank farm use. Second described application is hydrological gauging, including level and temperature monitoring of surface ponds and streams, and deep suspension of resistance gauges in small— diameter observation wells. Small profile, ease of sensor mounting, stability of level indication, low power requirement, and ease of signal utilization are shown to be provided for long-term hydrological data collection.