Is the automatic sprinkler system in the auxiliary alarm device. Is usually installed on the system partition of water distribution pipe or a water pipe, water flow of signals can be converted to electrical signals, the system monitors, alarm function. The flow indicator is composed of body, micro switches, paddles, flanges (or threads) links and so on. When the system is in a district of a fire when the water sprayer, water flow in the pipe network signal into electrical signal output, transmitted to the module or control center shows a fire position, regional police. When the shower stopped running, paddle Board automatic reset to servo alarm disappears.