Abstract: A system for detecting miswiring in an AC power supply for an appliance may comprise a voltage sensor sensing the voltage of a first hot line of the power supply for powering light electrical loads, a phase sensor sensing the phase difference between the first and a second hot line powering heavy electrical loads therebetween, and a control module coupling to the phase and voltage sensors. The control module may identify a first fault condition indicating that the second hot line and a neutral line are reversed when the voltage of the first hot line exceeds a threshold, and may identify a second fault condition indicating that the first hot line and the neutral line are reversed when the phase signal is within a phase threshold measured from 0 degrees. The system may disconnect different electrical loads from the power supply in the first and the second fault conditions.