A sensor module for a compressor having an electric motor connected to a power supply is provided. The sensor module includes: a first input connected to a first voltage sensor that generates a voltage signal corresponding to a voltage of the power supply; a second input connected to a first current sensor that generates a current signal corresponding to a current of the power supply; and a processor connected to the first and second inputs. The processor monitors the first and second inputs and, based on voltage measurements from the first input and current measurements from the second input, detects at least one of: (i) an unexpected variation of electric power from the power supply; and (ii) a mechanical malfunction. The processor is disposed within an electrical enclosure of the compressor, the electrical enclosure being configured to house electrical terminals for connecting the power supply to the electric motor.