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Dissolved Oxygen USB Data Logger
An affordable, precise data logger that measures oxygen concentrations in lakes, streams, rivers, estuaries, and coastal waters. Recommended for aquatic biology and hydrology research projects, this easy-to-maintain logger uses RDO® Basic (Rugged Dissolved Oxygen) optical DO sensor technology.
IMPORTANT INFORMATION
Requires HOBOware Pro software and either a U-DTW-1 Waterproof Shuttle or the Base-U-4 Optic USB Base Station for configuration and data offload.
Documentation
Data SheetUser Manual
Highlighted Features
- Affordable, high-performance dissolved oxygen (DO) monitoring with 0.2 mg/L accuracy
- Optical DO sensor technology for long-lasting calibration with less maintenance
- HOBOware Pro's Dissolved Oxygen Assistant software corrects for measurement drift from fouling; provides salinity-adjusted DO concentrations and percent saturation
- Optical USB interface for high-speed, reliable data offload
- User-replaceable DO sensor cap eliminates the need to send the logger back to the factory to replace the membrane
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 U20-001-04 Water Level logger.
Specifications
| Parameter | Value |
|---|---|
| Dissolved Oxygen | |
| Sensor Type | Optical |
| 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 |
| Resolution | 0.02 mg/L |
| Response Time | To 90% in less than 2 minutes |
| DO Sensor Cap Life | 6 months, cap expires 7 months after initialization |
| Temperature | |
| 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 |
| Logger | |
| 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) |
| Download Type | Optical |
| Depth Rating | 100 m (328 ft) |
| Buoyancy | Saltwater: 13 g (0.46 oz) negative | Freshwater: 20 g (0.71 oz) negative |
| 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 | 272.4 g (9.61 oz) |
| Environmental Rating | IP68 |
Applications
In what environment does this data logger operate?
This data logger operates in an underwater environment.
What measurements does this data logger support?
The U26-001 data logger supports the following measurements: Dissolved Oxygen and Temperature