Improving the Reliability of Diagnosing Reed Switch-Based Overcurrent Protection Circuits

This paper analyzes known circuitries of reed switch-based overcurrent protections. Notably, diagnostics-incapable circuitries tend to be unreliable as they issue false positives when reed switch contacts are stuck or when an element of the circuitry fails. Integrity diagnostics-featuring circuitries are not unflawed either. One is only able to diagnose its reed switch, the other one diagnoses everything but the reed switch, and the third one only features test diagnostics. Besides, the first two on the list may issue false positives when the diagnostic circuit is faulty. To improve the reliability of diagnosing reed switch-based overcurrent protections, the authors hereof developed a circuitry that checks the integrity of reed switches, protections, and its elements alike. The viability of this new design has been tested by thought experiments and computer simulations in Multisim 14.