Technical Characteristics and Versatility
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Integrated Flow Measurement: Beyond simple level tracking, the FMR20 includes built-in linearization tables. This allows the device to calculate and output flow rates for standard flumes and weirs, such as Parshall or Venturi channels, directly via its 4-20 mA HART signal.
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Dual Communication Options: The FMR20 provides flexibility in management. Users can perform commissioning and view signal curves wirelessly via Bluetooth using the SmartBlue app, or utilize standard HART communication for integration into existing control systems or remote displays.
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Superior Environmental Durability: The full PVDF housing is UV-resistant and chemically robust. With fully potted electronics and sealed wiring (IP66/IP68), the sensor is immune to water ingress, condensation, and flooding, ensuring long-term stability in outdoor environments like sewer shafts or open basins.
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Liquids and Solids Capability: While optimized for water and wastewater, the FMR20 is also suitable for basic solid applications up to 10m, such as small silos or stockpiles of minerals and building materials.
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Safe Remote Access: The Bluetooth functionality is certified for use even in hazardous areas. This allows maintenance teams to securely diagnose or configure sensors from a safe distance (up to 25m), eliminating the need for climbing onto tanks or entering confined spaces like manholes.
Technical Specification Matrix
| Feature | Technical Details |
| Measuring Principle | Free-space Radar (Time-of-Flight) |
| Frequency | 26 GHz (K-band) |
| Measuring Range | Liquids: 20m (66ft) / Solids: 10m (33ft) |
| Accuracy | Liquids: ±2mm (0.08″) / Solids: ±5mm (0.2″) |
| Process Temperature | -40 to +80°C (-40 to +176°F) |
| Process Pressure | -1 to +3 bar (-14.5 to +43 psi) |
| Communication | 4-20 mA HART, Bluetooth |
| Protection Class | IP66 / IP68 / NEMA 4X/6P |
Primary Applications
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Sewer Management: Reliable level monitoring in lift stations and pump shafts where steam, turbulence, or grease buildup might interfere with ultrasonic sensors.
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Open Channel Flow: High-accuracy head measurement in flumes and weirs for wastewater effluent or irrigation monitoring.
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Storage Tanks: Tracking levels of chemicals, liquid additives, or water in both metal and plastic tanks.
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Mining & Aggregates: Monitoring small bunkers and stockpiles of sand, gravel, or minerals.
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River Monitoring: Measuring water levels at bridges or embankments for flood warning systems.




