System Sensor WFD20N 2″ Water Flow Switch – NEMA 4, 450 PSI, UL/FM

System Sensor WFD20N 2″ Water Flow Switch – NEMA 4, 450 PSI

The System Sensor WFD20N is a rugged, vane-type water flow switch designed for wet-pipe fire sprinkler systems. Built with a NEMA 4 enclosure for indoor or outdoor use, it fits 2″ Schedule 7–40 steel pipe and is UL/FM listed for high reliability in demanding conditions.

Key Features:

• 2″ pipe compatibility (Schedule 7–40 steel)
• UL Listed & FM Approved
• 450 PSI maximum pressure rating
• Adjustable pneumatic retard (0–90 seconds)
• Dual SPDT switches – 10 A @ 125/250 VAC
• Weatherproof NEMA 4 enclosure for indoor/outdoor use
• Visual flow indicator and audible activation (73 dBA)
• Field-replaceable timer and switch assembly

Typical Applications:

• Wet fire sprinkler systems
• Riser rooms and pump stations
• Commercial fire protection monitoring

Specifications:

• Operating Temperature: 32°F to 150°F (0°C to 66°C)
• Flow Rate Sensitivity: 4–10 GPM
• Enclosure: NEMA 4 rated, tamper-resistant
• Conduit Openings: Two 1/2″ NPT (one open, one knock-out)
• Dimensions: Approx. 5.3″ x 3.8″ x 5.5″

Note: Mounts vertically or horizontally. Delay setting reduces false alarms due to surges or water hammer.