| 摘要 |
<P>PROBLEM TO BE SOLVED: To check the electric power limiting function of a charging circuit before an elevator is started. <P>SOLUTION: Control device of the elevator is equipped with a converter 11 to convert the AC power obtained from the AC main 3 into a DC power, a capacitor 12 to smooth the DC power, an inverter 16 to control a motor 17 upon converting the DC power into any arbitrary AC power, a contact 9 installed between the AC main 3 and the converter 11 and making the circuit when it is started, a first voltage sensing circuit 36 to sense the voltage of the capacitor 12, a charging circuit 34 to charge the capacitor 12 with DC-DC voltage conversion before the contact 9 is closed and having a power limiting part 34a, a discharging circuit 13 to discharge the capacitor 12 for a predetermined time through a resistance 14, and a control part 40 to open and close the contact 9 on the basis of the voltage value sensed by the first voltage sensing circuit 36 and determine that the power limiting part 34a is in failure if the threshold is attained by or exceeded upward by the voltage value when the discharging circuit 13 is operated for the prescribed period of time. <P>COPYRIGHT: (C)2007,JPO&INPIT |
