Measure oxygen concentrations in lakes, streams, rivers, estuaries, and coastal waters with the HOBO U26 Dissolved Oxygen Data Logger. This affordable and precise data logger is recommended for aquatic biology and hydrology research projects. The HOBO U26 uses RDO® Basic (Rugged Dissolved Oxygen) optical DO sensor technology and is easy to maintain.
Our HOBO U26 Dissolved Oxygen logger has been part of a multi-year evaluation of DO loggers and sensors by the Alliance for Coastal Technologies (ACT), and the results have just been published online. This provides an un-biased report of how our U26 performs in lab and field conditions. Note that our response letter with our added recommendations is attached at the end of this report on pages 58 and 59. Click here to read.
NOTE: For DO measurements in saltwater, an adjustment for salinity is required. For waters with small changes in salinity (<2 ppt), a salinity meter reading typically provides enough accuracy. For environments with greater salinity changes, we generally recommend the HOBO U24-002-C conductivity logger. If you need DO in Percent Saturation, barometric pressure data is required, which can be logged with a HOBO Water Level Data Logger (U20-001-04).
This data logger operates in an underwater environment.
The U26-001 data logger supports the following measurements: Dissolved Oxygen and Temperature
|Measurement Range:||0 to 30 mg/L|
|Calibrated Range:||0 to 20 mg/L; 0 to 35°C (32 to 95°F)|
|Accuracy:||± 0.2 mg/L up to 8 mg/L; ± 0.5 mg/L from 8 to 20 mg/L|
|Response Time:||To 90% in less than 2 minutes|
|DO Sensor Cap Life:||6 months, cap expires 7 months after initialization|
|Temperature Measurement/Operating Range:||-5 to 40°C (23 to 104°F); non-Freezing|
|Temperature Accuracy:||0.2°C (0.36°F)|
|Temperature Resolution:||0.02°C (0.04°F)|
|Response Time:||To 90% in less than 30 minutes|
|Memory:||21,700 sets of DO and temperature measurements (64 KB total memory)|
|Logging Rate:||1 minute to 18 hours|
|Time Accuracy:||±1 minute per month at 0 to 50°C (32 to 122°F)|
|Battery:||3.6 V lithium battery; factory replaceable|
|Battery Life:||3 years (at 5 minute logging)|
|Depth Rating:||100 m (328 ft)|
|Wetted Materials:||Black Delrin®, PVC, EPDM o-rings, silicone bronze screws; rated for saltwater use|
|Size:||39.6 mm diameter x 266.7 mm length (1.56 x 10.5 inches)|
|Weight:||464 g (16.37 oz)|