HOBO U20L Water Level Logger (U20L-0x) Manual
1-800-LOGGERS 2
www.onsetcomp.com
Specifications (continued)
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
Resolution
0.10°C at 25°C (0.18°F at 77°F), see Plot A
Response Time (90%)
10 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
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 acetal 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.
Environmental Rating
IP68
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%.
Plot A
