05159276 is referenced by 55 patents and cites 13 patents.

A leak detection system and method are disclosed. The capacitance of a leak detection cable is changed by a leaking liquid. A capacitance measuring circuit detects changes in the capacitance of the cable and thereby detects the presence of a leak. The capacitance measuring circuit includes an inverter, a current source, a comparator, and a timer. The inverter inverts a DC voltage to produce a mirror-image invented DC voltage. The current source produces a constant current proportional to the mirror image inverted DC voltage and supplies the constant current to the cable such that the cable is charged. A comparator compares the voltage across the cable to the input voltage and produces a match signal when they are equal. A timer which is responsive to the match signal measures the time required for the cable to be charged. The capacitance of the cable is directly proportional to the charge time.

Title
Capacitance measuring circuit and method for liquid leak detection by measuring charging time
Application Number
7/726479
Publication Number
5159276
Application Date
July 8, 1991
Publication Date
October 27, 1992
Inventor
William J Reddy III
Scottsdale
AZ, US
Agent
Gary A Samuels
Assignee
W L Gore & Associates
DE, US
IPC
H02G 15/28
G01R 31/08
G01R 31/02
G01R 27/26
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