US Patent:
20080013598, Jan 17, 2008
Inventors:
Jose M. Perotti - Merritt Island FL, US
Carlos T. Mata - Titusville FL, US
Josephine B. Santiago - Orlando FL, US
Peter Vokrot - Orlando FL, US
Carlos E. Zavala - Orlando FL, US
Bradley M. Burns - Titusville FL, US
Assignee:
USA as Represented by the Administrator of the National Aeronautics and Space Administration - Washington DC
International Classification:
G01K 7/00
Abstract:
Self-Validating Thermocouple (SVT) Systems capable of detecting sensor probe open circuits, short circuits, and unnoticeable faults such as a probe debonding and probe degradation are useful in the measurement of temperatures. SVT Systems provide such capabilities by incorporating a heating or excitation element into the measuring junction of the thermocouple. By heating the measuring junction and observing the decay time for the detected DC voltage signal, it is possible to indicate whether the thermocouple is bonded or debonded. A change in the thermal transfer function of the thermocouple system causes a change in the rise and decay times of the thermocouple output. Incorporation of the excitation element does not interfere with normal thermocouple operation, thus further allowing traditional validation procedures as well.
