| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensing device capable of distinguishing a sensor detection state transmitted from each slave unit from a detection state of the defective performance factor detecting part of a sensor with a simple configuration. SOLUTION: A slave unit BRk transmits a pulse NSk specified by on time NSonk=22k-2×T0 and off time NSoffk=22k-2×T0×3 in the case of detecting a detection object, and transmits a pulse NDk specified by on time NDonk=22k-1×T0 and off time NDoffk=22k-1×T0×3 in the case of detecting decrease of battery voltage. A master unit MS receives these pulses, and an on time measuring circuit ONT sequentially measures the on time of a plurality of pulses sequentially received by a receiving circuit REm in a prescribed measurement period based on an output of a timer TM, sequentially stores the measurement results into a storage circuit MEM and also transmits the end of the prescribed measurement period to a recognition circuit EXM. The recognition circuit EXM detects which slave unit detects an object and recognizes the battery residual quantity of which slave unit decreases on the basis of an output of the circuit ONT, the measured on time stored into the circuit MEM, etc.
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