Abstract: A high-diagnostic, dual sensor process temperature switch having a one-out-of-two voting architecture useful in commercial and industrial fluid transport systems is provided for determining whether process connections and isolation valves are plugged or closed, and for determining whether individual temperature sensors within the device are deformed, corroded or otherwise compromised. The dual temperature sensors functionally employ similar electronic technology, and are each disposed to provide variable electrical outputs to one of a plurality of discrete A/D converters. The dual temperature sensors' electrical outputs are compared prior to the A/D conversion process in order to immediately identify large temperature deviations between the respective sensors. Each of the A/D converters' digital signals are routed to one of a plurality of independent CPUs or data processors; the CPUs then generate digital output signals representing either a logical 0 (Low) or 1 (High).