Starting at $495.00
  • Call for availability



  • 32 to 140°F (0 to 60°C) fluid & ambient temperature
  • Normal flow range:
    • 1in: 1.30 to 50gal/min (4.92 to 180l/min)
    • 1.5in: 3.09 to 125gal/min (11.7 to 473l/min)
    • 2in: 5.13 to 200gal/min (19.4 to 757l/min)
  • Extended low flow range:
    • 1in: 0.26 to 1.30gal/min (0.98 to 4.92l/min)
    • 1.5in: 0.62 to 3.09gal/min (2.35 to 11.7l/min)
    • 2in: 1.03 to 5.13gal/min (3.90 to 19.4l/min)
  • ±2% of reading normal flow accuracy
  • Extended low flor range accuracy:
    • 1in: ±0.05gal/min (±0.19l/min)
    • 1.5in: ±0.13gal/min (±0.47l/min)
    • 2in: ±0.20gal/min (±0.76l/min)
  • Materials:
    • Body: glass filled nylon
    • Upper: polyphenylene oxide
  • 0.5 to 200Hz output frequency
  • 0 to 90% relative humidity, non-condensing
  • IP 68/NEMA 4X


The Dynasonics RS-900w Polymer Ultrasonic Flow Meter is suitable for outdoor use below grade, in submerged installations (<3ft of water for 24 hours), and pollution degree 4 environments. The low-maintenance construction contains no moving parts and is compatible with irrigation controllers. The meter comes in three sizes with NPT or BSP tapered threads, and NSF-certified options are available.

The RS-900w transmits ultrasonic signals through the moving water to measure the velocity of water flow. Two transducers generate and receive the ultrasound signals, one signal moving upstream and the other downstream. The difference in transit time equates to the velocity of water flowing through the pipe. The meter will not measure flow in partially filled or empty pipes. 

The meter is submersible and can be installed in horizontal or vertical pipes. To ensure a completely full pipe in a vertical installation, the flow should be in the up direction. Straight runs before or after the meter are not required.