| 摘要 |
PURPOSE:To make it possible to separate an uninterruptible power supply from a power system for maintainance without interrupting the uninterruptible power feed, by controlling first, second, and third electromagnetic switches that work in linkage with each AC switch of the uninterruptible power supply. CONSTITUTION:A switch 1 is provided between an AC power supply and a joining point on an AC-input side that connects an AC/DC converter with an AC switch 5, while a switch 2 is provided between a load and a joining point on an AC-output side, namely a load side, that connects a switch 4 with a switch 5. These electromagnetic switches 1 and 2 are used by turning on and off for connecting or disconnecting an uninterruptible power supply 20 with a power system. Moreover, a switch 3 is provided between the AC-power side of the switch 1 and the load side of the switch 2. A direct AC power feeding path from the AC power supply to the load is provided as a load feeding shunt path for a power supply 20. Consequently, the power supply 20 is separated from a power system surely to perform maintenance without interrupting the power feed for the load. |
