ALARM DEVICE

PROBLEM TO BE SOLVED: To make it clear which sensor detects is by displaying a lamp with an abnormal signal when abnormality of detected through a sensor, also holding the abnormal signal and displaying the lamp with the abnormal signal that is held when a signal is inputted by an external operation after lamp display is stopped. SOLUTION: An abnormal signal holding circuit 9 makes an output side that is linked with an F/F circuit 3 high level and also holds the state when an output of the circuit 3 is at high level and when one pulse signal is inputted through an OR circuit 8. When a reset switch 12 is turned on in this state, the ringing of a buzzer 6 is stopped. When a sensor 1 is normally restored by a clerk in charge, an abnormal signal deciding circuit 2 inverts an output signal from a high level to a low level and outputs a reset signal to the circuit 3. The circuit 3 inverts an output side from a high level to a low level, and a lamp display circuit 10 turns off a lamp 11 that is on. When the clerk turns on a switch 13, the lamp 11 which is turned off by the circuit 10 is turned on again.