MX2001 Bluetooth Water Level Loggers

The new HOBO® MX2001, the industry's first Bluetooth Low Energy (BLE) water level data logger, offers convenient wireless access to high-accuracy water level and temperature measurements - right from a mobile phone or tablet!

No need to take a laptop computer out to the field. No need to pull data loggers out of a well or push a button on the logger to download data. A mobile device and the MX2001 logger, with it's hassle-free non-vented design, are all that's required for easy deployment and readout. The MX2001 logger consists of a top-end unit and a water level sensor connected by a direct read cable. Cables can be ordered in lengths from 0.2 to 500m for deployment in a wide range of wells.

Key Advantages

  • Fast, easy wireless data offload to your mobile phone or tablet
  • No need to remove well caps, pull up loggers, or untangle cables
  • Works with Onset's free HOBOmobileTM app for iOS and Android
  • Includes barometric sensor for direct water level readout
  • Runs for one year on user-replaceable batteries
  • Fresh and salt water models available




  MX2001-04-S & MX2001-04-Ti-S MX2001-01-S & MX2001-01-Ti-S MX2001-02-S MX2001-03-S
Barometric Pressure (MX2001-TOP)
Temperature (All Sensor models)
Operation Range (sea level)
0-145kPa; approx. 0-4m of water 0-207kPa; approx. 0-9m of water  0-400kPa; approx. 0-30.6m of water 0-850kPa; approx. 0-76.5m of water 660 to 1070 mbar; -20° to 50°C -20° to 50°C
Factory Calibrated Range 69 - 145 kPa, 0° to 40°C 69 - 207 kPa, 0° to 40°C 69 - 400 kPa, 0° to 40°C 69 - 850 kPa, 0° to 40°C as above  
Burst Pressure 310 kPa or 18 m depth 310 kPa or 18 m depth 500 kPa or 40.8 m depth 1200 kPa or 112 m depth    
Water Level Accuracy* Typical: ±0.05% FS, 0.3cm
Maximum: ±0.1% FS, 0.6cm
Typical: ±0.05% FS, 0.5cm
Maximum: ±0.1% FS, 1.0cm
Typical: ±0.05% FS, 1.5cm
Maximum: ±0.1% FS, 3.0cm
Typical: ±0.05% FS, 3.8cm
Maximum: ±0.1% FS, 7.6cm
Typical: ±0.075% FS, 0.3cm
Maximum: ±0.15% FS, 0.6cm
Raw Accuracy** ±0.3% FS, 0.43 kPa maximum error ±0.3% FS, 0.62 kPa maximum error ±0.3% FS, 1.20 kPa maximum error ±0.3% FS, 2.55 kPa maximum error  ±2.0 mbar over full temperature range at fixed pressure; max. error ±0.5% FS  ±0.44°C from 0° to 50°C
Resolution <0.014 kPa, 0.14 cm water <0.02 kPa, 0.21 cm water 0.04 kPa, 0.41 cm water <0.085 kPa, 0.87 cm water  0.1 mbar 0.1°C at 25°C
Response Time (90%)*** <1 second at a stable temperature 1 second at a stable temperature  1 second at a stable temperature  1 second at a stable temperature 1 second at stable temperature 5 minutes in water (typical)
Stability (Drift)         0.1 mbar per year 0.1°C per year

*Water Level Accuracy: With accurate reference water level measurement, known water density, and a stable temperature environment. System Water Level Accuracy equals the sum of the Barometric Water Level Accuracy plus the selected sensor end Water Level Accuracy.

**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. There can be up to 0.5% of additional error due to rapid temperature changes. Measurement accuracy also depends on temperature response time.



  • Operation Range:-20° to 50°C 
  • Radio Power: 1 mW (0 dBm)
  • Transmission Range: Approximately 30.5 m (100 ft) line-of-sight
  • Wireless Data Standard: Bluetooth Low Energy (Bluetooth Smart)
  • Logging Rate: 1 second to 18 hours
  • Logging Modes: Fixed interval, multiple intervals with up to 8 user-defined logging intervals and durations, or burst
  • Memory Modes: Wrap when full or stop when full
  • Start Modes: Immediate, date & time, or next interval
  • Stop Modes:When memory full, stop with HOBOmobile, date & time, or after a set logging period
  • Time Accuracy:±1 minute per month 0° to 50°C
  • Battery: Two AA, 1.5 V alkaline batteries, user replaceable
  • Battery Life:1 year, typical with logging interval of 1 minute. Faster logging and/or statistics sampling intervals, entering burst logging mode, excessive readouts, checking of Full Status Details, and remaining connected with HOBOmobile will impact battery life.
  • Memory:256 KB memory (30,000 sets of measurements)
  • Full Memory Download Time: Approximately 2 minutes; may take longer the further the device is from the top end of the logger;
  • Diameter: 2.54 cm


HOBOMobile system requirements:

  • iOS 9.2 or 9.3
  • Android 4.4, 5.0, 5.1 or 6.0.1
  • Bluetooth 4.0
  • NOT currently compatible with Windows Mobile devices



About the manufacturer

Based on Cape Cod, Massachusetts, Onset has been designing and manufacturing its data loggers and monitoring solutions on site since the company's founding in 1981. Specialising in miniature, battery powered solutions, Onset data loggers are exceptional quality and value, ranging from indoor to outdoor and underwater applications. HOBO® data logger and weather station products are used around the world in a broad range of monitoring applications, from verifying the performance of green buildings and renewable energy systems to agricultural and coastal research.

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