Overview
A low-cost, research-grade data logger for continuous monitoring of water level and temperature at depths of up to 13, 30, or 100 feet in a wide range of underwater environments. This logger features 0.1% measurement accuracy, a polypropylene housing for use in both freshwater and saltwater, and a non-vented design for convenient and hassle-free deployment.
Features
Self-contained, non-vented design enables easy deployment
Ideal for use in both freshwater and saltwater environments, including wells, streams, lakes, wetlands, and tidal areas
Depths up to 13, 30, or 100 feet depending on model
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 U20-001-01 (freshwater) or U20-001-01-Ti (saltwater).
Specifications
Pressure (Absolute) and Water Level Measurements U20L-01
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, 0° to 40°C
10 to 30 psia, 32° to 104°F
Burst Pressure
310 kPa or 18 m depth
45 psia or 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 water
0.007 ft water
Pressure Response Time (90%)***
<1 second at a stable temperature; measurement accuracy also depends on temperature response time
Pressure (Absolute) and Water Level Measurements U20L-02
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) depth
Water Level Accuracy*
Typical error: ±0.1% FS, 3.0 cm (0.1 ft) water
Maximum error: ±0.2% FS, 6.0 cm (0.2 ft) water
Raw 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 at a stable temperature; measurement accuracy also depends on temperature response time
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
Temperature Measurements (All Models)
Operation Range
-20° to 50°C
-4° to 122°F
Accuracy
±0.44°C from 0° to 50°C , see manual for plot
±0.79°F from 32° to 122°F , see manual for plot
Resolution
0.10°C at 25°C , see manual for plot
0.18°F at 77°F , see manual for plot
Response Time (90%)
10 minutes in water (typical)
Stability (Drift)
0.1°C per year
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
CE Compliance Mark
What's In The Box
HOBO U20L-0x Water Level Data Logger
