Protector integrated with open phase protection, phase sequence protection and overvoltage/undervoltage protections

The utility model discloses a protector integrated with open phase protection, phase sequence protection and overvoltage/undervoltage protection, which comprises a plurality of functional unit circuits: a power circuit, a phase sequence and open phase protection circuit, an undervoltage protection circuit, an overvoltage protection circuit and a relay control circuit; the protector provided by the utility model has complete voltage protection functions, including protection for overvoltage, undervoltage, open phase and phase sequence abnormalities: overvoltage/undervoltage ranges can be adjusted, an overvoltage protection value can be set through a potentiometer RP2, and an undervoltage protection value can be set through a potentiometer RP1; overvoltage/undervoltage time delay ranges can be adjusted, the delay time of protection, i.e. the duration allowed by overvoltage/undervoltage, can be adjusted by a potentiometer RP4, the setting range is 0.5-5 seconds, or a potentiometer RP3 is adjusted to adjust the delay time between 1 second and 10 seconds; the protector provided by the utility model has open phase and phase sequence protection functions; if the phase sequences of a three-phase power supply are wrong in order, or the phenomenon of open phase occurs, the rectifier output voltage is boosted, and a light emitting tube L1 is lightened to indicate that the phase sequences are in disorder or the phenomenon of open phase exists.