The Hobo U24-002-C is a cost-effective data logger for measuring salinity, conductivity and temperature in saltwater environments with relatively small changes in salinity (±5,000 μS/cm) such as saltwater bays, or to detect salinity events such as upwelling, rainstorm, and discharge events. Data from the logger can be used with data from the Hobo U26 dissolved oxygen logger for monitoring percent dissolved oxygen saturation.
This data logger has a non-contact sensor which provides a long life and it has a easy access to the sensor for cleaning and shedding air bubbles. Two user-selectable ranges provide measurements from 100 to 55,000 uS/cm. The Delrin housing will not corrode in saltwater and the HOBOware Pro software enables start/end-point calibration to compensate for any fouling and provides easy conversion to specific conductance and salinity using the Practical Salinity Scale 1978 (PSS-78).
Via the USB optical interface you can offload in high-speed the reliable salinity data in wet environments and it is also compatible with the Hobo waterproof shuttle for easy and reliable data retrieval and transport.
The HOBO U24 conductivity/salinity data logger features a non-contact sensor with a titanium pentoxide coating. This coating prevents the sensor from coming in contact with the water, which in turn prevents tarnishing or corrosion associated with traditional electrode sensors. This sensor coating is also inert, enabling fouling to be easily wiped off the sensor.
This data logger operates in outdoor and water environments and the data logger supports the following measurements: conductivity/salinity and temperature.
Measurements: actual conductivity, temperature, Specific Conductance at 25C (calculated), salinity (calculated using PSS-78, the Practical Salinity Scale 1978)
Conductivity measurement range (calibrated range): high range: 5.000 to 55.000 uS/cm, low range: 100 to 10.000 uS/cm (over the range of 5 to 35°C)
Temperature measurement range: 5 to 35°C
Specific conductance accuracy (in calibrated range using conductivity assistant and calibration measurements): low range: 3% of reading or 50 µS/cm, high range: 5% of reading, in waters within a range of ±3.000 µS/cm: waters with greater variation can have substantially greater error.
Temperature accuracy: 0.1°C at 25°C
Conductivity drift: up to 12% sensor drift per month, exclusive of drift from fouling. Monthly start- and end-point calibration should be used with the HOBOware conductivity assistant to achieve the specified specific conductance accuracy.
Response time: 1 second to 90% of change (in water)
Operating range: -2 to 36°C – non-freezing
Memory: 18.500 temperature and conductivity measurements when using one conductivity range: 11.500 sets of measurements when using both conductivity ranges (64 KB total memory)
Sample rate: 1 second to 18 hrs, fixed or multiple-rate sampling with up to 8 user-defined sampling intervals
Battery life: 3 years (with 1 minute logging)
Maximum depth: 70 meters