Master unit and automatic fire alarm system

摘要

PROBLEM TO BE SOLVED: To reduce capacity of a secondary battery used as a standby power source.SOLUTION: A master machine 1 comprises a reception part 14, a determination part 171, an adjustment part 172, and a current limit circuit 112. The reception part 14 receives a signal transmitted from a slave machine 2. The determination part 171 determines whether or not fire occurs according to the signal received on the reception part 14. The adjustment part 171 adjusts a current which flows between a pair of electric wires 31, 32. The current limit circuit 112 lowers the current flowing between the pair of electric wires 31, 32 and limits the current. The adjustment part 171 controls the current limit circuit 112 and limits the current flowing between the pair of electric wires 31, 32, when a current value of the current flowing between the pair of electric wires 31, 32 reaches a fire notification level which is used in determination on the determination part 171, and reaches a threshold.SELECTED DRAWING: Figure 1