| 摘要 |
PROBLEM TO BE SOLVED: To improve reliability by reducing a possibility of a signal collision even when the number of alarm units is increased.SOLUTION: The alarm system comprises: a first channel group 14-1 including home fire alarm units 10-1 through 10-3; and a second channel group 14-2 including home fire alarm units 10-4 through 10-6. Different communication frequencies are set for the respective groups. The alarm units 10-1 and 10-4 of the respective groups are assigned as relay home fire alarm units. The relay home fire alarm units 10-1 and 10-4 of the respective groups are connected to each other via wired alarm transfer signal lines 16-1 and 16-2. If the home fire alarm unit 10-1 of the first channel group 14-1 detects a fire, an alarm transfer signal is transmitted to the home fire alarm unit 10-4. The home fire alarm unit 10-4 converts the received alarm transfer signal into a fire event signal having its own channel frequency and sending the signal through wireless transmission for having the alarm units 10-4 through 10-6 of the second channel group 14-2 perform an interlocking alarm. Each channel group may be provided with a master unit and slave units so that the master units of the respective groups are interconnected via alarm transfer signal lines for relay transmission. |
