| 摘要 |
PROBLEM TO BE SOLVED: To provide a fire alarm system for surely and quickly and easily checking the availability of radio communication while suppressing the increase in the consumption of a battery. SOLUTION: When receiving a message for check transmitted from each slave unit TRi, a control part 1 of a master unit TR1 of a fire alarm system starts the count-down of a prescribed cycle 2×Tk(k=1 to 4) obtained by doubling individual periods T1 to T4 by slave unit TRi, and starts a radio transmission/reception part 2 when each count-down ends. When any message for check transmitted from the salve unit TRi corresponding to each of the individual cycles T1 to T4 can not be received, the control part 1 of the master unit TR1 determines that the radio communication of the slave unit TRi which has not received any message for check is disabled. COPYRIGHT: (C)2011,JPO&INPIT |
