GF P51530-P1 Standard Installed Paddle Wheel Flow Sensor

Model P51530-P1 is the GF Signet 515 Rotor-X insertion paddlewheel flow sensor, engineered for liquid flow monitoring in medium-to-large pipelines with DN125 to DN200 (5" to 8"). It adopts a self-powered passive paddlewheel measurement principle, serving as an economical general-purpose flow probe widely used in water treatment, chemical processing and pure water industries.

• Sensor body: Glass-filled polypropylene (PP), resistant to acids, alkalis, seawater and mild chemical corrosion
• Rotor paddle: PVDF, outstanding wear resistance and chemical compatibility
• Central shaft: Titanium alloy, high tensile strength, rust-free, suitable for media containing tiny solid particles
• Sealing O-ring: Standard FPM (Viton); EPDM or Kalrez special seals are optional
• Cable: Standard 7.6 m twisted shielded cable, extendable up to 60 m, effectively suppressing on-site electromagnetic interference

• Flow velocity range: 0.3 ~ 6 m/s (1 ~ 20 ft/s), turndown ratio up to 20:1 for stable measurement under both low and high flow rates
• Applicable pipe size: DN125 ~ DN200 (5" ~ 8"); the full series covers DN15 ~ DN900 pipelines
• Accuracy: Linear tolerance ±1% FS, repeatability ±0.5% FS at 25°C ambient temperature
• Minimum Reynolds number: 4500; only for full-pipe liquid applications, not compatible with gas or partially filled pipes
• Output signal: Passive sine wave frequency signal (1 V peak-to-peak); output 6 Hz per 1 ft/s flow velocity. No external power supply required. Directly compatible with passive flow indicators (e.g. 3-5090). Can be paired with Model 2760 preamplifier to connect to PLCs or transmitters (5500, 5600, 8850 series, etc.)
• Temperature & pressure rating (PP housing):

  Max operating pressure: 12.5 bar at 20°C

  Max medium temperature: 90°C; pressure rating drops to 1.7 bar at 90°C

• Mounting type: Insertion installation. Compatible with tees, saddle clamps and welded bosses. Supports hot-tap installation under pressure without system shutdown.

1. Self-powered passive design simplifies wiring

   No external power supply needed. Passive sine wave output cuts wiring costs significantly, ideal for remote monitoring points without power access.

2. Broad chemical compatibility

   Combination of PP housing, PVDF rotor and titanium shaft works well with pure water, wastewater, acid/alkaline solutions, seawater and circulating cooling water.

3. Wide turndown ratio for versatile working conditions

   20:1 wide measurement range ensures reliable detection at low velocity of 0.3 m/s and avoids excessive abrasion at maximum 6 m/s, covering variable-load production lines with one single sensor.

4. Low maintenance and long service life

   No electronic components submerged in process media; only the paddlewheel rotates. Titanium shaft resists jamming and abrasion, minimizing disassembly and calibration cycles during long-term continuous operation.

5. Flexible installation for large pipelines

   Specially optimized for 5"–8" industrial pipes. Matched with complete GF fitting accessories, enabling hot-tap installation without draining or stopping the pipeline.

6. High precision and excellent repeatability

   ±0.5% repeatability delivers consistent long-term data, perfectly suited for flow metering, pump protection and flow interlock control systems.

Pure water / RO reverse osmosis systems, wastewater treatment, circulating cooling water, chemical fluid transfer, power plant water circulation systems