| 摘要 |
PROBLEM TO BE SOLVED: To provide a warning device improved in induction resistant noise performance and induction resistant voltage performance. SOLUTION: Concerning a warning device 1, a switch SW1 is provided for selecting one of supervisory mode for monitoring various kinds of equipment, warning supervisory mode for monitoring a warning and operation display mode for displaying operating conditions and when a non-voltage contact signal is inputted at the time of warning supervisory mode in the state of opening the switch SW1, a warning is detected by flickering an LED, sounding a buzzer or operating a relay for move. Only ringing of the buzzer is stopped by pressing a buzzer stop switch SW3 during the indication of this warning and when the non-voltage contact signal is inputted at the time of operation display mode in the state of short-circuitting the switch SW1, a warning is reported by turning on the LED. Since the indication of a test based on closing of a switch SW2 for testing the defect of the LED is displayed while being turned on/off corresponding to setting of the supervisory mode, the defect of a lamp or the like can be confirmed simultaneously with the setting conditions of the supervisory mode. The input part of the non-voltage contact signal of such a warning device 1 is provided with a protection circuit against induction noise and induction voltage composed of one resistor R1 and two diodes D1 and D2.
|
