OBS-3+ Turbidity Sensor

The OBS-3+ Turbidity Monitor is a submersible probe, part of our OBS® line of products that use a backscatter method to measure turbidity. The OBS-3+ operates in the range of 0 to 4000 NTU. It replaces the OBS3 on our price lists.
The OBS-3+ can be used in several applications, ranging from water quality in freshwater rivers and streams to sediment transport and dredge monitoring. The output for the OBS-3+ can be specified at time of order, allowing you to customize the sensor to match the datalogger being used to make the measurement.
Features
Each OBS-3 has two channels—one channel measures the lower turbidity range and the other channel measures the higher turbidity range.
-2.5
Supports our CR200-series, CR510, or CR10(X) dataloggers. Both channels have an output range of 0 to 2.5 V.
-5
Supports our CR800, CR850, CR1000, CR3000, CR5000, and CR9000(X) dataloggers. Both channels have an output range of 0 to 5 V.
-20
One channel has an output range of 4-20 mA, and the other channel has an output range of 0 to 5 V. A CURS100 is required for our dataloggers to read the 4-20 mA output.
Specifications
Maximum Depth: 500 m (1640.5 ft ) with stainless-steel body; 1500 m (4921.5 ft ) with titanium body
Drift: less than 2% per year
Maximum Data Rate: 10 Hz
Input Voltage
Voltage Output: 5 to 15 Vdc
Current Output (4-20 mA): 9 to 15 Vdc
Typical Current Drain
Voltage Output: 15 mA
Current Output (4-20 mA): 45 mA
Infrared Wavelength: 850 nm ±5 nm
Daylight Rejection: -28 dB (re:48 mWcm²)