The HOBO U20L-004 is a low-cost, research-grade water level data logger for continuously measuring water level and temperature in a wide range of underwater environments. It features 0.1% measurement accuracy, a polypropylene housing for use in both fresh and salt water, and a non-vented design for convenient and hassle-free deployment.
- Self-contained non-vented design enables easy deployment
- Ideal for use in both fresh and saltwater environments, including wells, streams, lakes, wetlands, and tidal areas
- Depths up to 13 feet
- Durable ceramic pressure sensor withstands freezing
- HOBOware Pro software provides easy conversion to accurate water level reading, fully compensated for barometric pressure, temperature, and water density
Note: A calibration certificate is not offered for this logger. If you require a NIST-traceable calibration certificate, please see the U20-001-04 (freshwater) or U20-001-04-Ti (saltwater).In what environment does this data logger operate?
This data logger operates in outdoor and underwater environments.
What measurements does this data logger support?
The U20L-04 data logger supports the following measurements: Absolute Pressure, Barometric Pressure, Temperature and Water Level
The country of origin for this product is the United States. To see the full specifications for this product, please see our product manual found under the documentation tab if available.
|Pressure (Absolute) and Water Level Measurements U20L-04|
|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: ±0.1% FS, 0.4 cm (0.013 ft) water
Maximum error: ±0.2% FS, 0.8 cm (0.026 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 at a stable temperature; measurement accuracy also depends on temperature response time|
|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 manual|
|Resolution||0.10°C at 25°C (0.18°F at 77°F), see Plot A in manual|
|Response Time (90%)||10 minutes in water (typical)|
|Stability (Drift)||0.1°C (0.18°F) per year|
|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||Approximately 154 g (5.43 oz) in air Approximately 53.9 g (1.9 oz) in fresh water|
|Dimensions||3.18 cm (1.25 inches) diameter, 15.24 cm (6.0 inches) length; mounting hole 6.3 mm (0.25 inches) diameter|
|Wetted Materials||Polypropylene housing and lanyard; Viton and Buna-N O-rings; ceramic sensor in acetyl end cap; stainless steel screws suitable for saltwater|
|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 the HOBOware User’s Guide for details.|
|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 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 20 minutes in water to achieve full temperature compensation of the pressure sensor. Maximum error due to rapid thermal changes is approximately 0.5%.