| 摘要 |
A temperature excursion sensor and locator consisting of a temperature sensitive cable which includes two electrical conductors separated by a dielectric member to form a linear strip capacitor wherein at least one of the conductors is comprised of a number of thermostatic devices connected serially. An over or under temperature excursion is sensed and located by the cable when it is connected from either end to control electronics by measuring the capacitance of the cable. Under normal conditions, all of the thermostatic devices are electrically conducting and the control electronics measures the full capacitance. Upon occurrence of a temperature excursion, one or more thermostatic devices become non-conductive and the resulting measured capacitance is proportionately reduced. Presence of the temperature excursion is sensed and its location indicated by the control electronics which compares the full cable capacitance to the reduced capacitance, the ratio of said capacitances determining the location of the temperature excursion.
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