| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas alarm where alarm concentration is not changed even if drive voltage supplied to a gas sensor changes.SOLUTION: A gas sensor 1 outputs sensor output Vs corresponding to gas concentration of gas to be detected. Drive voltage Vd is supplied to the gas sensor 1 from a voltage source 2. A CPU 31 generates an alarm by using an alarm buzzer 41 and an alarm lamp 42 when the sensor output Vs from the gas sensor 1 becomes an alarm value or above. A drive voltage detection circuit 20 detects the drive voltage Vd supplied to the gas sensor 1. The CPU 31 sets the alarm value on the basis of the drive voltage Vd detected by the drive voltage detection circuit 20. |
