Waterflow switches are devices used in fire protection systems to detect the flow of water within the system. They play a crucial role in signaling the activation of the fire sprinkler system in response to the flow of water, indicating a potential fire incident. There are two main types of waterflow switches: vane-type switches and pressure switch-type switches. According to NFPA 25, waterflow switches are tested semiannually by flowing water through the test connection. The alarm signal activates within 90 seconds of water flow, triggered by conditions like an activated sprinkler head, leaks, or pressure differences.
Additional Resource: NFPA 25