PURPOSE: To supply stable power to a landing terminal device by compensating a voltage drop in a cable changed by an operating condition of an elevator.
CONSTITUTION: A plurality of power supplies 3A to 3C are provided between the top floor and the lowest floor, to also detect voltage of a landing terminal device most distant from each power supply, that is, of the largest voltage drop, and power supply output voltage is adjusted in accordance with a detection value of the terminal device voltage. Thus, since a cable voltage drop can be compensated by controlling the power supply, by obviating correspondence of enlarging a sectional area of a cable, increasing the number of the cables, etc., it is advantageous in view of the structure and cost.
ONUKI AKIRA
KOMATSU TSUTOMU
HITACHI MITO ENG KK
Next Patent: ELEVATOR LANDING LEVEL DETECTOR