Part Numbers
U20L-04 • U20L-01 • U20L-02
HOBO Water Level Data Logger
From $360.00 USD
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; for use in freshwater or saltwater.
Important Information
Requires HOBOware Pro software and either a U-DTW-1 Waterproof Shuttle or the Base-U-4 Optic USB Base Station for configuration and data offload. Please see compatible items below.
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.
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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).
Country of Origin
United States
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°C10 to 30 psia, 32° to 104°F
- Burst Pressure
-
310 kPa or 18 m depth45 psia or 60 ft depth
- Water Level Accuracy*
-
Typical error: ±0.1% FS, 1.0 cm (0.03 ft) waterMaximum 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 water0.007 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 plot0.18°F at 77°F , see manual for plot
- Response Time (90%)
-
10 minutes in water (typical)
- Stability (Drift)
-
0.1°C per year0.18°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 airApproximately 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
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Compatible items
Data Offload - Base Stations - Shuttles - Couplers
Protective Enclosures
Stainless Steel Cable/Crimps
Well Caps
Compliance Certificates
Data Offload - Base Stations - Shuttles - Couplers
Graphing & Analysis
What's in the box
- HOBO U20L-0x Water Level Data Logger
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