Description
The WFDN Series waterflow detectors consist of a rugged, NEMA 4-rated enclosure that is more damage-resistant than previous metal designs. The waterflow detector is designed for both indoor and outdoor use, with the widest available temperature range, from 32°F to 150°F. They are also approved for installation on the widest range of pipe schedules; sizes 2 in. through 4 in. are approved for installation on pipe schedules 7 through 40.
UL-listed models are equipped with tamper-resistant cover screws to prevent unauthorized entry. Inside, two sets of SPDT (Form C) synchronized switches are enclosed in a durable terminal block with a new layout designed to make wiring easy. The wire-ready terminals and COM terminals are on a different elevation, with a large barrier between switches and easy-to-read, raised, textured lettering, all making wiring easy. An optional cover tamper switch is available and securely snaps into place, requiring no tools.
The WFDN series incorporates a mechanical time delay feature, which minimizes the risk of false alarms due to pressure surges or air trapped in the fire sprinkler system. The larger and easy-to-turn timer dial makes setting the waterflow detector simple, with high-contrast, pad-printed markings. The dial offers three tabs to help with turning, with one larger tab located at the dial position for approximately 60 seconds. A notch on the dial indicates approximately 30 seconds, making the detector easy to set in dimly lit locations.
The WFDN series is designed for accuracy and repeatability. The detector also offers improved performance during vibration in riser applications where detectors are exposed to a large in-rush of water.