W-DO Dissolved Oxygen Sensor

The dissolved oxygen sensor is an interchangeable sensor that works with the HOBO MX800 series water loggers to measure dissolved oxygen and temperature.

The dissolved oxygen sensor can be connected directly to the fully submersible MX801 model, or connected by cable to the direct-read MX802 model, which does not require removing the sensor from the water to download the data.

When this sensor is connected to a HOBO MX800 logger that also has a conductivity or CTD sensor connected, the logger can directly log salinity-adjusted DO. With this sensor connected to the HOBO MX802 direct-read model, the logger can directly calculate DO percent saturation. When used with the fully submersible HOBO MX801 model, a barometric logger data file (from an MX802 logger or MX2001) is needed to calculate DO percent saturation, for post-processing in the HOBOconnect app. In waters with changing salinity, the logger must also have a salinity sensor connected or will need an MX800 salinity data file to obtain DO percent saturation.

Features

• The user-replaceable dissolved oxygen cap lasts 2 years or more
• High-accuracy measurements, even without calibration
• Get salinity-adjusted dissolved oxygen directly when used with a conductivity sensor (W-CT or W-CTD), with no need for post-processing
• Direct dissolved oxygen percent saturation data, with no need for post-processing (when used with MX802)
• Easy calibration with the included calibration sleeve: saves time
• 1" diameter for use in narrow wells (with cable to the MX802 above the well)
• The PVC housing withstands salt water

Specifications

Dissolved oxygen

Optical sensor: (dynamic luminescence quenching)

Measurement range: 0 to 60 mg/L; 0-600% saturation

Accuracy: Out of the box: ±0.2 mg/L (typical) in the range of 0 to 20 mg/L

±4% in the range of 20 to 60 mg/L

With user calibration: ±0.1 mg/L in the range of 0 to 20 mg/L; ±2% in the range of 20 to 60 mg/L

Resolution: 0.01 mg/l

Sensor drift: Accuracy is maintained for 2 years; apart from the effects of fouling.

Response time: To 90% in less than 45 seconds.

Dissolved oxygen sensor cap life: 2 years; after this time, the sensor will continue to work, but possibly with less accuracy.

Temperature

Temperature measurement/operating range: From -5 to 50 °C (from 23 to 104 °F), non-freezing.

Temperature accuracy: 0.15 °C (0.27 °F)

Temperature resolution: 0.01 °C (0.04 °F)

Response time: to 90% in less than 15 minutes

Logging rate: when this sensor is used, the maximum logging rate is 1 minute

Depth rating: IP-68, waterproof up to 100 m (328 feet) - must be connected to the logger and have the dissolved oxygen sensor cap installed

Wetted materials: black Delrin®, PVC, EPDM O-rings, suitable for use in salt water

Markings: The CE marking identifies this product as compliant with all relevant directives of the European Union (EU).