Waterflow alarm

Another t) e waterflow alarm is the electric bell at the riser. This would be initiated by a vane type water flow alarm in the riser or a pressure switch on the retard chamber. The vane alarm can be electrically dampered and the pressure switch will utilize a retard chamber on a alarm check valve to dampen surges. The electric bell is less desirable than the water motor gong since it requires electricity where the water motor gong is self-energized. 

When a Are occurs, the heat produced will fuse a sprinkler, causing water to flow. The waterflow indicator is activated by the water flow. The paddle, which normally lies motionless inside the pipe, is forced up, thereby activating the pneumatic time delay mechanism, which closes or opens a microswitch after the preset retard time has elapsed. This action causes an electric alarm to sound. The alarm will continue to sound as long as there is a flow of water in the system. The water will flow until it is shut off manually. 

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