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.

Each OBS-3 has two channels—one channel measures the lower turbidity range and the other channel measures the higher turbidity range.
Supports our CR200-series, CR510, or CR10(X) dataloggers. Both channels have an output range of 0 to 2.5 V.
Supports our CR800, CR850, CR1000, CR3000, CR5000, and CR9000(X) dataloggers. Both channels have an output range of 0 to 5 V.
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.