Safe Torque Off (STO) means that power capable of causing rotation is not applied to the motor. STO technology is applied to the elevator of the AC or DC motor powered and controlled by static components, and the safety control of the motor is realized by cutting off the power supply of the motor. STO adopts a dual-channel circuit architecture, the safety integrity level reaches SIL3, and the hardware fault margin is 1. Combined with the real-time comparison of the dual-channel status, it ensures that the control of the motor is safe and reliable. STO replaces the contactor to control the motor, and has the advantages of low noise, small size, and fast response.

Brake safety control refers to the use of safety circuits containing electronic components to achieve safety control of the brake. The brake control is combined with the power supply, and the safe brake control is realized through the safe control of the brake power supply. The brake control unit adopts the design structure of double actuators, and the independent state monitoring of the double agencies makes the control of the brake safe and reliable. The safety circuit replaces the control mode of the contactor to the brake, and has the advantages of fast response and long life.

Electronic star sealing refers to the way of limiting the unexpected moving speed of the car by short-circuiting the three-phase winding of the motor by using the existing power module of the inverter in the safe torque off state. The real-time detection of electronic star-sealing circuit fully guarantees the pre-diagnosis of circuit faults and the effectiveness of star-sealing control. The electronic star sealing replaces the hardware star sealing method of the contactor, and has the advantages of small size, fast response and more reliability.

The contactless system solution not only promotes the technological innovation of elevator products, but also essentially solves the problems encountered in practical applications, which has far-reaching significance.