The OBS-3A combines our OBS probe with pressure, temperature, and conductivity sensors in a battery-powered recording instrument. Batteries and electronics are contained in a housing capable of operating at depths of up to 300 meters—depending on the pressure sensor installed. (OBS® is a registered trademark of Campbell Scientific.)Read More
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 gage, 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.
|Maximum Submersion Depth||300 m (984 ft)|
|Operating Temperature Range||0° to 35°C|
|Storage Temperature Range||-20° to +70°C|
|Drift over Time||< 2% per year|
|Drift over Temperature||0.05% per °C|
|Maximum Sample Size||2048|
|Sampling Rate||1 to 25 Hz (when connected to a PC)|
|Maximum Data Rate||5 Hz|
|Data Capacity||8 MB|
|Maximum Number of Data Lines||200,000|
|PC Interfaces||RS-232/115 kbps, RS-485/115 kbps|
|Battery Capacity||18 Ahr|
|Maximum Battery Life||8,000 h|
|Infrared Wavelength||850 nm|
|Maximum Concentration Range||
|Pressure Measurement Range||0 to 10, 20, 50, 100, or 200 m|
|Turbidity Measurement Range||0.4 to 4,000 NTU|
|Conductivity Measurement Range||0 to 65 mS/cm (40 PSU, o/oo)|
|Pressure Accuracy||±0.5% of f.s. (where f.s. = 50, 100, or 200 dBar)|
|Turbidity Accuracy||< 2%|
|Diameter||7.6 cm (3.0 in.)|
|Length||36.2 cm (14.3 in.)|
|Weight||1.5 kg (3.4 lb)|
Campbell Scientific offers a choice of field cables used to connect the OBS-3A to a PC for system configuration. The cables differ in their length. The ResourceDVD shipped with the OBS-3A includes the HydroSci support software.
HydroSci is used to configure and extract data from the CRS45X Recording Submersible Pressure Transducer and the OBS-3A Turbidity and Temperature Monitoring System.View Update History
Adds Chinese language support for version 1.2 of HydroSci.
Note: Language support for the above listed version only.