Patent attributes
An elevator door control system comprises a door sensor, a door motor control unit, a transmission unit being wired by a cable as part of or all of a transmission path between the door sensor and the door motor control unit, a storage unit to store a change in a binary signal indicating detection of an obstacle in association with a door position at a time of the change in the binary signal. A partially broken state of the cable is determined by evaluating reproducibility of the door position at the time of the change in the binary signal on the basis of the timing of the change in the binary signal and a door position at the time of the change in the binary signal. The partially broken state of the cable caused by repeated bending deformation of the cable can be determined.
