| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power backup system which can performs backup operation for a long time with a battery of smaller size without causing a system stop even if trouble occurs to an in-use system device as to system relief by a backup power source in case of a power failure. SOLUTION: An AC-DC converting circuit 6 converts the power of the commercial power source into a DC voltage needed to charge the in-use system device 3, a standby system device 4, a control part 1, and a battery 5. When a break of the commercial power source is detected in the AC-DC converting circuit 6, information on the break of the commercial power source is sent out to a control part 1. The control part 1 once receiving the information on the commercial power source break from the AC-DC converting circuit 6 supplies the electric power from the battery 5 to only the in-use system device 3 and does not supply the electric power to the standby system device 4. While the power supply is switched to the battery 5, the control part 1 stops supplying the electric power from the battery 5 to the in-use system device 3 if detecting a fault of the in-use system device 3 and starts supplying the electric power from the battery 5 to the standby system device 4.</p> |
