HOBO U20 Water Level Data Logger - U20-001-04

Sensor location drawing Barometric Pressure Compensation Assistant Demo Multi-rate Sampling Demo

Providing a narrow range of measurement for the best possible accuracy, this version is ideal for monitoring water levels and temperatures in wells, streams, lakes and wetlands.

Like other HOBO Water Level Data Loggers, the 13-foot version offers exceptional value and ease-of-use, with no cumbersome vent tubes or desiccants to maintain. The HOBO Water Level Titanium is recommended for saltwater deployment for recording water levels and temperatures in brackish wetlands and tidal areas.

View how the HOBO Water Level Logger compares to the Competition.

Pressure Sensor
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 altitude

Factory 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) water

Raw 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

Thermal response time (90%): † Approximately 10 minutes in water to achieve full temperature compensation of the pressure sensor

Temperature Sensor
Operation range: -20° to 50°C (-4° to 122°F)

Accuracy: 0.37°C at 20°C (0.67°F at 68°F), see Plot A

Resolution: 0.1°C at 20°C (0.18°F at 68°F) (10-bit), see Plot A

Response time (90%): 3.5 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)

Dimensions: 2.46 cm (0.97 inches) diameter, 15 cm (5.9 inches) length; mounting hole 6.3 mm (0.25 inches) diameter

Weight: Approximately 210 g (7.4 oz)

Wetted materials: 316 stainless steel (for use in freshwater), Viton® o-rings, acetyl cap, ceramic sensor

Shock/drop: Logger is sensitive to shocks. Handle with care and avoid any impact. Always use proper packaging when shipping the logger.

Logging 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 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.

The CE Marking identifies this product as complying with the relevant directives in the European Union (EU).

* With accurate reference water level measurement and Barometric Compensation Assistant data
** Absolute pressure sensor accuracy includes all pressure drift, temperature, and hysteresis-induced errors

† Maximum error due to rapid thermal changes is approximately 0.5%

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