The MX20L Water Level Logger brings you all the same great features as the U20L and more!
Integrating Bluetooth for fast and reliable data download, the MX20L logger eliminates the need to plug your logger into a base station or shuttle to offload data in the field, ensuring continuous water level and temperature monitoring. With options to measure at depth ranges of 13, 30, or 100 feet in a wide range of underwater environments, this rugged logger features 0.1% measurement accuracy, a durable polypropylene housing for use in both freshwater and saltwater, and a non-vented design for convenient and reliable deployment.
The MX20L comes with a magnetic activation fob that can "wake up" the logger to activate its Bluetooth communication for configuration and data download. The included fob comes with a lanyard to prevent losing or dropping the fob in the field.
This logger records absolute pressure, which is later converted to water level readings by our HOBOconnect software. To compensate for barometric pressure changes, you can use another HOBO MX20L Water Level logger as a barometric reference. See our FAQ section for more information.
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
- Depth measurement options of up to 13, 30, or 100 feet depending on model
- Durable ceramic pressure sensor withstands freezing
- Streamlined data offload via Bluetooth to the free HOBOconnect app
- HOBOconnect app provides easy extraction and visulization of water level data
- Extended battery life up to 10 years (power-saving mode requires magnetic fob to activate Bluetooth for data download)
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 MX20L-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 MX20L-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 MX20L-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
±0.2°C from 0° to 50°C
±0.36°F from 32° to 122°F
Resolution
0.10°C at 25°C
0.18°F at 77°F
Response Time (90%)
10 minutes in water (typical)
Stability (Drift)
0.1°C per year
0.18°F per year
Logger
Wireless Standard
Bluetooth 5 LE
Transmission Range
Approximately 30.5 m (100 ft) line-of-sight
Radio Power
1mW (0 dBm)
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)
3 years with 1-minute logging and Bluetooth always on
7 years with 1-minute logging and Bluetooth off and LED off
10 years with 5-minute logging and Bluetooth off and LED off
Battery Indication
Battery status shown in HOBOconnect app (approximate)
Memory (Non-volatile)
Approximately 400,000 sets of pressure and temperature measurements
Data Download Time (with Bluetooth 5+ devices)
Full Memory: Approximately 3.5 minutes
1000,000 measurements < 1 minute
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 Modes
Fixed-interval (normal or statistics), burst or multiple intervals with up to 8 user-defined intervals and durations; logging intervals from 1 second to 18 hours. Refer to the HOBOconnect User’s Guide for details.
Start Modes
Immediate, next interval, date & time, button start (fob or app)
Stop Modes
Memory full, never stop (overwrite oldest data), date & time, or after set logging period
Pause
Pause and restart with HOBOconnect app
Alarms
Log high- or low-alarm events; alarm status shown in HOBOconnect app
Environmental Rating
IP68
* Water Level Accuracy: With accurate reference water level measurement, known water density, accurate barometric compensation 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%.
