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OVERVIEW
Monitor Changing Water Levels with the U20 Logger
Records water level and temperature in depths from 4m to 76m; narrow range provides best accuracy in shallow waters. Available in stainless-steel for shallow wells, streams, lakes, and freshwater wetlands and in titanium for saltwater/brackish wetlands and tidal areas.
The HOBO U20 Water Level Logger is used for monitoring changing water levels in a wide range of applications including streams, lakes, wetlands, tidal areas, and groundwater. The loggers are typically deployed in existing wells or stilling wells installed specifically for deploying the loggers. This logger features high accuracy at
a great price and HOBO ease-of-use, with no cumbersome vent tubes or desiccants to maintain.The logger uses a maintenance-free absolute pressure sensor and features a durable stainless steel or titanium housing (depending on model) and ceramic pressure sensor. The HOBO Water Level Titanium is recommended for saltwater deployment for recording water levels and temperatures in wetlands and tidal areas. The logger uses precision electronics to measure absolute pressure and temperature and has enough memory to record over 21,700 combined pressure and temperature measurements.
Features
- Lightning protection – no long signal wires, and electronics are shielded in a metal housing
- HOBOware Pro software provides easy conversion to accurate water level reading, fully compensated for barometric pressure, temperature, and water density
- Multiple-rate sampling allows faster sampling at critical times such as when pumping starts or stops
- Available in four depth ranges
- Ideal for use in wells, streams, lakes, wetlands, and tidal areas
- No-vent-tube design for easy reliable deployment
- Available in stainless and titanium versions
- Durable ceramic pressure sensor
- 3-point NIST-traceable calibration certificate included
Important Information
Requires HOBOware Pro software and either a U-DTW-1 Waterproof Shuttle or the Base-U-4 Optic USB Base Station for configuration and data offload. Please see related items below.
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SPECIFICATIONS
Pressure (Absolute) and Water Level Measurements U20-001-01 and U20-001-01-Ti
Operation Range 0 to 207 kPa (0 to 30 psia); approximately 0 to 9 m (0 to 30 ft) of water depth at sea level, or 0 to 12 m (0 to 40 ft) of water at 3,000 m (10,000 ft) of altitude Factory Calibrated Range 69 to 207 kPa (10 to 30 psia), 0° to 40°C (32° to 104°F) Burst Pressure 310 kPa (45 psia) or 18 m (60 ft) depth Water Level Accuracy* Typical error: ±0.05% FS, 0.5 cm (0.015 ft) water
Maximum error: ±0.1% FS, 1.0 cm (0.03 ft) waterRaw Pressure Accuracy** ±0.3% FS, 0.62 kPa (0.09 psi) maximum error Resolution <0.02 kPa (0.003 psi), 0.21 cm (0.007 ft) water
Pressure Response Time (90%)*** <1 second; measurement accuracy also depends on temperature response time
Pressure (Absolute) and Water Level Measurements U20-001-02 and U20-001-02-Ti
Operation Range 0 to 400 kPa (0 to 58 psia); approximately 0 to 30.6 m (0 to 100 ft) of water depth at sea level, or 0 to 33.6 m (0 to 111 ft) of water at 3,000 m (10,000 ft) of altitude Factory Calibrated Range 69 to 400 kPa (10 to 58 psia), 0° to 40°C (32° to 104°F) Burst Pressure 500 kPa (72.5 psia) or 40.8 m (134 ft) dept Water Level Accuracy* Typical error: ±0.05% FS, 1.5 cm (0.05 ft) water
Maximum error: ±0.1% FS, 3 cm (0.1 ft) waterRaw Pressure Accuracy** ±0.3% FS, 1.20 kPa (0.17 psi) maximum error Resolution <0.04 kPa (0.006 psi), 0.41 cm (0.013 ft) water Pressure Response Time (90%)*** <1 second; measurement accuracy also depends on temperature response time Pressure (Absolute) and Water Level Measurements U20-001-03 and U20-001-03-Ti
Operation Range 0 to 850 kPa (0 to 123.3 psia); approximately 0 to 76.5 m (0 to 251 ft) of water depth at sea level, or 0 to 79.5 m (0 to 262 ft) of water at 3,000 m (10,000 ft) of altitude Factory Calibrated Range 69 to 850 kPa (10 to 123.3 psia), 0° to 40°C (32° to 104°F) Burst Pressure 1200 kPa (174 psia) or 112 m (368 ft) depth Water Level Accuracy* Typical error: ±0.05% FS, 3.8 cm (0.125 ft) water
Maximum error: ±0.1% FS, 7.6 cm (0.25 ft) waterRaw Pressure Accuracy** ±0.3% FS, 2.55 kPa (0.37 psi) maximum error Resolution <0.085 kPa (0.012 psi), 0.87 cm (0.028 ft) water Pressure Response Time (90%)*** <1 second; measurement accuracy also depends on temperature response time Pressure (Absolute) and Water Level Measurements U20-001-04 and U20-001-04-Ti
Operation Range 0 to 145 kPa (0 to 21 psia); approximately 0 to 4 m (0 to 13 ft) of water depth at sea level, or 0 to 7 m (0 to
23 ft) of water at 3,000 m (10,000 ft) of altitudeFactory Calibrated Range 69 to 145 kPa (10 to 21 psia), 0° to 40°C (32° to 104°F) Burst Pressure 310 kPa (45 psia) or 18 m (60 ft) depth Water Level Accuracy* Typical error: ±0.075% FS, 0.3 cm (0.01 ft) water
Maximum error: ±0.15% FS, 0.6 cm (0.02 ft) waterRaw Pressure Accuracy** ±0.3% FS, 0.43 kPa (0.063 psi) maximum error Resolution <0.014 kPa (0.002 psi), 0.14 cm (0.005 ft) water Pressure Response Time (90%)*** <1 second; measurement accuracy also depends on temperature response time Temperature Measurements (All Models)
Operation Range -20° to 50°C (-4° to 122°F) Accuracy ±0.44°C from 0° to 50°C (±0.79°F from 32° to 122°F), see Plot A in User Manual Resolution 0.10°C at 25°C (0.18°F at 77°F), see Plot A in User Manual Response Time (90%) 5 minutes in water (typical) Stability (Drift) 0.1°C (0.18°F) per year Logger
Real-time Clock ± 1 minute per month 0° to 50°C (32° to 122°F) Battery 2/3 AA, 3.6 Volt lithium, factory-replaceable Battery Life (Typical Use) 5 years with 1 minute or greater logging interval Memory (Non-volatile) 64K bytes memory (approx. 21,700 pressure and temperature samples) Weight Stainless steel models: approximately 210 g (7.4 oz)
Titanium models: approximately 140 g (4.8 oz)Dimensions 2.46 cm (0.97 inches) diameter, 15 cm (5.9 inches) length; mounting hole 6.3 mm (0.25 inches) diameter Wetted Materials Stainless Steel models: 316 stainless steel, Viton® O-rings, acetal cap, ceramic sensor
Titanium models: Titanium, Viton O-rings, acetal cap, ceramic sensorLogging Interval Fixed-rate or multiple logging intervals, with up to 8 user-defined logging intervals and durations; logging intervals from 1 second to 18 hours. Refer to the HOBOware software manual. Launch Modes Immediate start and delayed start Offload Modes Offload while logging; stop and offload Battery Indication Battery voltage can be viewed in status screen and optionally logged in datafile. Low battery indication in datafile. Environmental Rating IP68 CE The CE Marking identifies this product as complying with all relevant directives in the European Union (EU). * Water Level Accuracy: With accurate reference water level measurement, known water density, accurate Barometric Compensation Assistant data, and a stable temperature environment.
** Raw Pressure Accuracy: Absolute pressure sensor accuracy includes all sensor drift, temperature, and hysteresis-induced errors.
*** Changes in Temperature: Allow 10 minutes in water to achieve full temperature compensation of the pressure sensor. Maximum error due to rapid thermal changes is approximately 0.5%.
HOBO® U20 Series Water Level Loggers
$1,390.00 – $1,715.00 ex GST
The HOBO Water Level data logger features high accuracy at a great price and ease-of-use, with no cumbersome vent tubes or desiccants to maintain. This data logger is ideal for recording water levels and temperatures in shallow wells, streams, lakes and freshwater wetlands. For saltwater deployments, such as brackish wetlands and tidal areas, see HOBO U20 Water Level Titanium.
