Highlighted Features
Lightning protection - no long signal wires, and electronics are shielded in stainless steel housing for use in freshwater (see the Water Level logger sensor location drawing)
HOBOware Pro software provides easy conversion to accurate water level reading, fully compensated for barometric pressure (see demo) temperature, and water density.
Multiple-rate sampling (see demo) allows faster sampling at critical times such as when pumping starts or stops.
Available in 4 depth ranges
Ideal for use in wells, streams, lakes, wetlands and tidal areas
No-vent-tube design for easy reliable deployment
Available in stainless and titanium versions
Durable ceramic pressure sensor
3-point NIST-traceable calibration certificate included
The U20-001-04 data logger supports the following measurements: Absolute Pressure, Barometric Pressure, Temperature and Water Level
| Pressure and Water Level Measurements U20-001-04 and U20-001-04-Ti |
| 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: ±0.075% FS, 0.3 cm (0.01 ft) water
Maximum error: ±0.15% FS, 0.6 cm (0.02 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; 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 (±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%) |
5 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 |
Stainless steel models: approximately 210 g (7.4 oz)
Titanium models: approximately 140 g (4.8 oz) |
| Dimensions |
2.46 cm (0.97 inches) diameter, 15 cm (5.9 inches) length; mounting hole 6.3 mm (0.25 inches) diameter |
| Wetted Materials |
316 stainless steel, Viton® o-rings, acetyl cap, ceramic sensor |
| 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 software manual. |
| 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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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.
