Motor soft starter with intelligent by-pass control function

The utility model discloses a motor soft starter with intelligent by-pass control function. The motor soft starter includes a central processing unit, a thyristor and a trigger circuit thereof, a by-pass alternating current contactor spliced with the thyristor, an input keyboard and a display which are connected with the central processing unit, and also a current detecting circuit that respectively detects the current I in a major power supply loop of the thyristor in real time. The central processing unit is a microprocessor control system that correspondingly determines the deferred action time t of the by-pass alternating current contactor according to I/Ie and correspondingly controls the deferred action of the by-pass alternating current contactor, wherein the Ie is the rated current of the started motor. The circuit control design is reasonable, the use and operation are simple. The motor soft starter can intelligently control the deferred action time of the by-pass alternating current contactor.