Open wire detection system and method

Abstract

An open-wire detection system and method includes a current transmitter that can be connected to one or more wires, wherein the current transmitter provides a minimum current and/or a current that is greater than the minimum current. An anti-aliasing filter is connected to an analog-to-digital converter, such that the anti-aliasing filter receives the minimum current provided by the current transmitter and provides an output signal to the analog-to-digital converter. A noise filter is generally connected to an open-wire threshold detector, wherein the noise filter and the open-wire threshold detector permit detection of input levels below the minimum current provided by the current transmitter. An output from the open-wire threshold detector can be sampled multiple times at intervals that correlate with a frequency of a plurality of digital signals to produce sampled data, such that if the sampled data is below the minimum current, one or more of the wires (e.g., a return field wire and/or a field wire connected to a power supply) is reported as constituting an open-wire.