Regardless of the cable and its installation method, it is difficult to avoid short circuit between the wire and the wire due to the falling object, metal corrosion, aging of the wire insulation, etc. during the use of the elevator, and the short circuit belongs to Soft faults, it is difficult to control the time of its occurrence, and an accident occurs when the elevator door is opened at the elevator stop.

In the current elevator design, the door lock circuit of the elevator hall is part of the safety circuit and is relatively independent. The general installation method adopts the manner that all the main and auxiliary door interlocking contacts of each layer are connected in series. However, if the above-mentioned door lock circuit is short-circuited, the elevator will continue to operate without closing the door.

Therefore, it is recommended to adopt the method of splitting the main and auxiliary door lock circuits, that is, the installation mode of the main door interlock circuit device is unchanged, and the sub-door interlocking devices of each floor are connected in series into a single auxiliary door lock circuit in the hoistway to lead to the electric control of the machine room. After the cabinet is connected into the safety loop, the distance between the pipeline and the main lock loop must be greater than 200mm before entering the main tunnel of the hoistway when installing the auxiliary interlock circuit on the hoistway wall.

Such a failure of the two door lock circuits at the same time and causing the door lock circuit failure causes the elevator accident to be minimized. That is to say, the double door lock circuit increases the safety of the safety circuit, and the safety of the elevator is greatly improved!