| 摘要 |
An alarm system including a sensor for providing an output signal upon sensing a given condition, an alarm unit for providing an alarm signal on receipt of the output signal, and a timer, coupled between the sensor and the alarm unit, which is reset to a preset count each time it receives an indication that the sensor has detected the given condition where the timer is allowed to count down from a preset count while no sensor is providing output signals and an arming signal is generated by the timer when it completes the countdown. |
