A Ab bs st tr ra ac ct t The Plan and equipment of vertical lifting are very important in high-rise building construction site, and unmanned lifts usage is increasing for financial and efficient reason. However if lift stop position error occur, It can be accumulated. And the lift can not be available during an engineer fix the problem. So loss of time and cost will occur when lifts have problems. This paper reports an improved lift stop position sensing device for preventing loss of time and

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... st from lift stop position error. The result of tests showed that the system has a correction function of lift stop position error, and the accuracy of device which was developed in this paper was about 9.75mm better than existing equipment.