Patent ID: 6704682
Filing Date: 2004-03-09
Classification: G05B

Abstract:
A dual sensor process pressure switch having a one-out-of-two voting architecture, said switch comprising:a first pressure sensor for sensing a first process pressure in a fluid transport valve, and for outputting a first analog sensor signal to each of a sensor input comparator and a first analog/digital converter; a second pressure sensor for sensing a second process pressure in a fluid transport valve, and for outputting a second analog sensor signal to each of a sensor input comparator and a second analog/digital converter; a sensor input comparator for receiving said first analog sensor signal from said first pressure sensor, and for receiving said second analog sensor signal from said second pressure sensor; a first analog/digital converter for receiving said first analog sensor signal from said first pressure sensor, and for converting said first analog sensor signal into a corresponding first digital sensor signal and then sending said first digital sensor signal to a first CPU; a second analog/digital converter for receiving said second analog sensor signal from said second pressure sensor, and for converting said second analog sensor signal into a corresponding second digital sensor signal and then sending said second digital sensor signal to a second CPU; a first CPU for receiving said first digital sensor signal, and for generating a first logical output signal based on a predetermined set point and then sending said first logical output signal to an integrated diagnostics unit; and a second CPU for receiving said second digital sensor signal, and for generating a second logical output signal based on a predetermined set point and then sending said second logical output signal to an integrated diagnostics unit; an integrated diagnostics unit for receiving said first logical output signal from said first CPU and said second logical output signal from said second CPU, and for communicating with a master diagnostics switch to generate a switch control signal responsive to said first logical output signal and said second logical output signal; a master diagnostics switch for communicating with said integrated diagnostics unit to generate a switch control signal responsive to said first logical output signal and said second logical output signal, and for outputting said switch control signal to a plurality of servant diagnostics switches; and a plurality of servant diagnostics switches responsive to a control signal received from said master diagnostics switch.