A low arc AC contactor comprises an on/off mechanism electromagnetic-controlled contact, a pulse power source generating circuit, a low arc trigger generating circuit, and a multifunctional fault-detecting circuit. The contactor converts an instantaneous strong current into strong pulse magnetic field energy to actuate contacts of mechanical portion of the contactor, so that the power source load is on or off. Each of the actuating process will be controlled by the electric circuit to perform at the lowest potential of AC voltage for reducing arc's destructive power. Moreover, the contactor uses photoelectric coupling circuits, in which it can be controlled by external low voltage signal commands, as well as providing protection from overload, phase loss, short circuit, and leakage current.
