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HYDROLAB is a leading US manufacturer that introduced the first Multi-Parameter Sonde to the world in 1968. For more than 45 years, Hydrolab has designed and manufactured multi-parameter sondes for water quality monitoring in the environment. Hydrolab is now part of the Hach Hydromet and OTT Hydromet family.

At the heart of Hydrolab multi-probes is our superior sensor technology, which ensures that the important data you collect is solid, reliable, and dependable. In addition, our sensors are built to last, and comes packaged in a rugged, non-corrosivehousing so your total cost of ownership is ultimately the lowest in the industry.

Its reliability, ease-of-use, and metadata produce water quality data


Its reliability, ease-of-use, and metadata produce water quality data


  • Self-monitoring system reports the status of the instrument, flags the data, and shows the user where the problem is with assistance on how to solve the issue
  • User-scheduled calibration and maintenance intervals indicate when they are due
  • Guided and semi-automated calibration routines lead the user through the calibration process
  • Calibration results are stored with date and time, calibration type, user identification, and user notes
  • Check Calibration process allows the user to verify calibration and store the results
  • Calibration reports contain information about previous calibrations and calibration checks
  • Sensor status is saved with every line of data and is contained in the log file
  • Dedicated communications modules allow easy integration with data loggers and telemetry systems
  • Compatible with the Surveyor HL – a fully IP67 handheld designed for field use with a full-color screen that is visible in direct sunlight


SensorsTemperature sensor and up to four additional sensors plus depth and ORP
External6 ... 30 VDC (12 VDC nominal) applied to the communications module,
12 VDC: 250 mW average, 19 W peak
Internal(Optional) Internal alkaline D-cell battery, non-rechargeable.
Sleep mode at 12 V20 mA
CommunicationsHydrolab communications modules: USB, SDI-12, RS232, RS485, or TTY
Memory4 GB of internal memory; 1 second interval minimum
User Interface
PC SoftwareHydrolab Operating Software
Handheld(Optional) Hydrolab Surveyor HL
Sonde Depth Rating200 m (656 ft)
Maximum Deployment Cable200 m (656 ft)
Diameter w/o bumpers4.4 cm (1.75 in.)
Diameter with bumbers5.3 cm (2.1 in.)
Weight with internal battery pack (IBP) and storage/calibration cup2.2 kg (5 lb)
Length - no IBP, standard sensor guard51.4 cm (20.25 in.)
Length - no IBP, extended sensor guard66.4 cm (26.125 in.)
Length - IBP and standard sensor guard62.2cm (24.5 in.)
Length - IBP and extended sensor guard77.8 cm (30.625 in.)
Environmental conditions
Operating temperature-5 ... 50 °C (23 ... 122 °F), non-freezing
Storage temperature1 ... 50 °C (34 ... 122 °F)


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