The HOBO U20L-01 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.
This data logger requires either the HOBO Waterproof Shuttle or the Universal Optic USB Base Station for configuration and data offload, HOBOware software (free download). NOTE: HOBOware Pro is required when using the U-DTW-1 Waterproof Shuttle.
HOBOware Pro software provides easy conversion to accurate water level reading, fully compensated for barometric pressure,temperature, and water density
This data logger operates in outdoor and underwater environments.
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 40C (32 to 104F)
Burst Pressure
310 kPa (45 psia) or 18 m (60 ft) depth
Water Level Accuracy*
Typical error: 0.1% FS, 1.0 cm (0.03 ft) water Maximum error: 0.2% FS, 2.0 cm (0.06 ft) water
Raw 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 at a stable temperature; measurement accurac
Temperature Measurements
Operation Range
-20 to 50C (-4 to 122F)
Accuracy
0.44C from 0 to 50C (0.79F from 32 to 122F), see Plot Ain manual
Resolution
0.10C at 25C (0.18F at 77F), see Plot Ain manual
Response Time (90%)
10 minutes in water (typical)
Stability (Drift)
0.1C (0.18F) per year
Logger
Real-time Clock
1 minute per month 0 to 50C (32 to 122F)
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 Users 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.
