| 摘要 |
PROBLEM TO BE SOLVED: To determine whether a battery returns to a normal voltage, while suppressing consumption of the battery due to battery monitoring, and also to suppress consumption of the battery due to alarm of battery abnormality.SOLUTION: A fire alarm includes: a battery 11; a battery monitoring unit 13 determining occurrence of battery abnormality when a battery voltage lowers to a threshold voltage or less by measuring the battery voltage for each monitoring interval; and an alarm unit 14 performing battery abnormality occurrence alarm when battery abnormality occurs. The fire alarm also includes a monitoring interval setting unit 13a that sets a monitoring interval before occurrence of battery abnormality to a first monitoring interval, and sets a monitoring interval after occurrence of battery abnormality to a second monitoring interval longer than the first monitoring interval.SELECTED DRAWING: Figure 1 |
