| 摘要 |
PURPOSE: A tamper switch for sensing the opening and closing of a fire fighting valve is provided to improve the lifetime thereof semi-permanently by adopting a hall sensor. CONSTITUTION: A tamper switch for sensing the opening and closing of a fire fighting valve comprises a valve (10), a fire signal receiver (20), and a valve stem (13). The tamper switch is installed in the valve stem of a fire fighting valve to transfer an electrical signal to the fire signal receiver or a control unit by sensing the opening and closing of the fire fighting valve installed in a water supply pipe. A water supply unit includes a water supply valve. The opening and closing of the fire fighting valve is detected from the fire signal receiver, then an alarm sounds or light flickers. [Reference numerals] (20) Fire signal receiver |
