| 摘要 |
PROBLEM TO BE SOLVED: To enable longtime backup by a battery at power interruption and to improve operability. SOLUTION: When an abnormal state is detected by a sensor, circuits required for notification to outside are devided into a group A and the other circuits are devided into a group B. When main power interruption is detected, power is supplied from a battery 5 by a power supply part 11. The device maintains an ordinary state by estimating time when power recovery is expected by a clock 21 and supplying the power to both groups A and B during the time. When a specified time is passed due to the lasting power interruption, the life of the battery is prolonged by turning a power switching circuit 13 off and stopping power supply to the group B. After that, the device returns to an ordinary operation by supplying the power to the group B when the abnormal state is detected by the sensor 2 and performs required processings. |
