SonTek CastAway-CTD

What We Love About the CastAway-CTD

Price$7,100.00 (US Only)


In Stock 0 - Available for Backorder

Designed for coastal profiling, the CastAway-CTD® incorporates a 6-electrode conductivity cell coupled with a fast response thermistor to provide highly accurate, high-resolution CTD measurements to depths of 100 m. Now Integrated with HYPACK!

  • Overview

    Field Ready and Rugged

    The CastAway-CTD is a small, rugged, and technically advanced CTD designed for profiling to depths of up to 100 m. The system incorporates modern technical features which allow it to achieve a 5 Hz response time, fine spatial resolution, and high accuracy. It uses a six electrode flow-through conductivity cell with zero external fields and a rapid response thermistor to attain high measurement accuracy. The instrument is simple to deploy, does not require a pump, and is hydrodynamically designed to free fall at a rate of 1 m/s.

    The integrated real-time data display screen, internal GPS sensor, and automated wireless data transfer are unique features that simplify data collection.

    • Salinity Accuracy: 0.1 PSU
    • Temperature Accuracy: 0.05°C
    • Small size
    • Integrated GPS position
    • Real-time display screen
    • Wireless data transfer
    • 5 Hz sampling rate

    Each CastAway-CTD cast is referenced with time and location using its built-in GPS receiver. Latitude and longitude are acquired both before and after each profile. Plots of conductivity, temperature, salinity, and sound speed versus depth can be viewed immediately on the CastAway's integrated color LCD screen in the field. Raw data can be easily downloaded via Bluetooth to a Windows computer for detailed analysis and /or export.

    CastAway New York

    *US Patent #8272262

    A quick reminder:  you will want to get your CastAway-CTD calibrated annually to:

    • Maintain high-accuracy conductivity and temperature data;
    • Keep data to spec and avoid the possibility of drift, impacting accuracy;
    • Ensure your CastAway is clean and free of dirt, oil, salt buildup, and environmental contamination.

    Turnaround time is about 2-3 weeks. For more information and to schedule an appointment, contact SonTek Customer Support.

    CastAway Alaska

  • Specifications
    Parameter Specifications   
    Range        Resolution       Accuracy      Method      
    Conductivity 0 to 100,000 µS/cm      1 µS/cm 0.25% ±5 µS/cm      Measured
    Density 990 to 1035 kg/m3 0.04 kg.m3 ± 0.02 kg/m3 EOS80••
    Depth 0 to 100 m 0.01 m ±0.25% FS EOS80••
    GPS - - 10m -
    Pressure 0 to 100 dBar 0.01 dBar 0.25% of FS Measured
    Salinity Up to 42 0.01 ±0.1 PSS-78
    Sound Speed 1400 –1730 m/s 0.01 m/s ±0.15 m/s Chen-Millero‡  
    Specific Conductivity§ 0 to 250,000 µS/cm 1 µS/cm 0.25% ±5 µS/cm EOS80••
    Temperature -5 to +45°C 0.01°C ±0.05°C Measured

    Based on temperature resolution and accuracy.
    ••International Equation of State for seawater (EOS-80).
    1978 Practical Salinity Scale
     Chen-Millero, 1977. Speed-of-sound in seawater at high pressures.
    § Based on 100,000 µS/cm at -5°C.


    Internal BlueTooth Radio (Class 2)
    Up to 10m range

    Dimensions — Diameter 7.11 cm | 2.8 in
    Dimensions — Height

    20.32 cm | 8.0 in

    Dimensions — Weight 0.45 kg | 1.0 lbs
    Power 2 Standard AA batteries for 40+ hours of operation
    Recorder 15 MB recorder
    Good for 750+ casts during typical use
    Sample Rate 5Hz
  • Accessories
  • Software

    CastAway-CTD Software - V 1.5

    The CastAway-CTD basic software was designed specifically for the CastAway-CTD system and is used to communicate with the instrument, download data, configure the instrument, upgrade the CastAway-CTD's firmware, in addition to offering a suite of data visualization, management and exporting capabilities.

    CastAway-CTD Firmware - V 1.63

    The CastAway-CTD is a profiling instrument that measures conductivity, temperature, and pressure. Its embedded firmware controls all of the instrument's functions and assures the data is of the utmost quality. This firmware is free to any CastAway-CTD owners/users and does not require any activation code. Please follow the instructions in the CastAway-CTD manual for details on how to check the version of your instrument's current firmware version and how to upgrade it if necessary.

    Get the Software and Firmware

  • Video

    What We Love About the CastAway-CTD

    What isn't there to love about the CastAway-CTD? Xylem employees from around the world talk about some of their favorite features of SonTek's powerful, pint-size CTD!

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