Benefits and Features

Runs 1,500 to 8,000 hours on three D-cell batteries

Monitors sediment concentrations up to 5,000 mg/l and turbidity up to 4,000 NTUs

Uses the field-proven OBS® technology (U.S. Patent No.4,841,157) to measure turbidity

Logs instrument depth, wave height, wave period, temperature, and salinity

Records 200,000 lines of data in flash memory

Programs set points and sampling times

Offers an optional 5-point sedimentation calibration

Technical Description

The heart of the OBS-3A monitoring system is an OBS sensor for measuring turbidity and suspended solids concentrations. This sensor detects near infrared (NIR) radiation scattered from suspended particles.

A fast-response, stainless steel-clad thermistor monitors temperature. Pressure is measured with a semiconductor piezoresistive strain gauge, and conductivity is measured with a four-electrode conduction-type cell. Working depths of the pressure sensor are selected as an option. (See the Ordering Info on the web page.)

The monitor uses HydroSci software running under Windows XP, 7, and 8.