HOBO® U20 Water Level
Logger (U20-001-0x and U20-001-0x-Ti) Manual
12315-H MAN-U20
The HOBO U20 Water Level Logger is used for monitoring changing water levels in a
wide range of applications including streams, lakes, wetlands, tidal areas, and
groundwater. The loggers are typically deployed in existing wells or stilling wells
installed specifically for deploying the loggers. This logger features high accuracy at
a great price and HOBO ease-of-use, with no cumbersome vent tubes or desiccants
to maintain.
The logger uses a maintenance-free absolute pressure sensor and features a
durable stainless steel or titanium housing (depending on model) and ceramic
pressure sensor. The HOBO Water Level Titanium is recommended for saltwater
deployment for recording water levels and temperatures in wetlands and tidal
areas. The logger uses precision electronics to measure absolute pressure and
temperature and has enough memory to record over 21,700 combined pressure
and temperature measurements.
Specifications
Pressure (Absolute) and Water Level Measurements U20-001-01 and U20-001-01-Ti
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 40°C (32° to 104°F)
Burst Pressure
310 kPa (45 psia) or 18 m (60 ft) depth
Water Level Accuracy*
Typical error: ±0.05% FS, 0.5 cm (0.015 ft) water
Maximum error: ±0.1% FS, 1.0 cm (0.03 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; measurement accuracy also depends on
temperature response time
Pressure (Absolute) and Water Level Measurements U20-001-02 and U20-001-02-Ti
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:
±
0.05% FS, 1.5 cm (0.05 ft) water
Maximum error:
±
0.1% FS, 3 cm (0.1 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; measurement accuracy also depends on
temperature response time
Pressure (Absolute) and Water Level Measurements U20-001-03 and U20-001-03-Ti
Operation Range
0 to 850 kPa (0 to 123.3 psia); approximately 0 to 76.5 m (0 to
251 ft) of water depth at sea level, or 0 to 79.5 m (0 to 262 ft)
of water at 3,000 m (10,000 ft) of altitude
Factory Calibrated Range
69 to 850 kPa (10 to 123.3 psia), 0° to 40°C (32° to 104°F)
Burst Pressure
1200 kPa (174 psia) or 112 m (368 ft) depth
Water Level Accuracy*
Typical error:
±
0.05% FS, 3.8 cm (0.125 ft) water
Maximum error:
±
0.1% FS, 7.6 cm (0.25 ft) water
Raw Pressure Accuracy**
±
0.3% FS, 2.55 kPa (0.37 psi) maximum error
HOBO Water Level Logger
Models:
•
U20-001-01 (30-foot depth)
and U20-001-01-Ti (30-foot
depth/Titanium)
•
U20-001-02 (100-foot depth)
and U20-001-02-Ti (100-foot
depth/Titanium)
•
U20-001-03 (250-foot depth)
and U20-001-03-Ti (250-foot
depth/Titanium)
•
U20-001-04 (13-foot depth)
and U20-001-04-Ti (13-foot
depth/Titanium)
Required Items:
•
Coupler (COUPLER-2-B) with
USB Optic Base Station
(BASE-U-4)
or
HOBO Waterproof Shuttle
(U-DTW-1)
•
HOBOware
®
Pro
Accessories:
•
Cable (CABLE-1-300 or
CABLE-1-50) and Cable Crimp
(CABLE-1-CRIMP)
•
Replacement Coupler
(COUPLER2-B)
