The waterflow detectors mount to water-filled pipes in fire sprinkler systems. When water flow rate in the pipe is 10 gallons per minute or more, the flow force will deflect the vane of the detector, which produces a switched output, usually after a specified delay. The switch will not actuate if the flow rate is less than 4 gallons per minute.
With a pneumatically controlled mechanical delay mechanism equipped in the detector, the output may retard for a specified period that preset according to the requirements. Delays do NOT accumulate, they would reset if the flow of water stops or drops below minimum triggering flow rate.
