| 摘要 |
PURPOSE: To surely prevent a battery from entering an overdischarged state by deciding whether the power switch of a power consuming machine is turned on or off correctly upon power interruption and interrupting the battery of an uninterruptible power supply when the power switch is turned off. CONSTITUTION: The uninterruptible power supply 10 comprises a circuit 12 for interrupting a battery 1b and a power consuming machine 11, and a circuit 13 for controlling the operation of the interruption circuit 12. The control circuit 13 actuates the interruption circuit 12 when a power interruption detection signal is outputted from a power interruption detection circuit 16 but a power supply 11b in the power consuming machine 11 produces no output. Since the power supply 11b produces an output when the power switch 11a of the power consuming machine 11 is turned on/off, the state of the power switch 11a can be determined correctly. When power supply is interrupted and the power switch 11a is turned off, the battery 1b and the power consuming machine 11 are interrupted thus preventing the battery 1b from entering an overdischarged state. |
