Idronaut - Model OCEAN SEVEN 308 -CTD Logger
TEMPERATURE SENSOR
The OS308 CTD is equipped with a 4Gbyte data memory, which allows the storing of about 250 millions data sets, each one being composed of the reading of all the installed sensors plus the acquisition date and time. Different types of battery can be installed in the CTD housing. The battery endurance is considerably extended, because the OS308 enters a deep sleep mode between acquisitions and drains only 4μAh from the battery. For instance, by monitoring every hour, the OS308 (CTD only) can run for about 9 years on a single Lithium size “C” cell.
Features a very fast platinum resistance thermometer (response time: 50 ms). Negligible self-heating effect. Optionally combined C/T sensor featuring a 7ms fast thermistor (20 ms after processing) integrated in the conductivity cell is available upon request.
CONDUCTIVITY CELL
The high accuracy seven platinum ring quartz conductivity cell (patented) can be cleaned in the field without the need for recalibration. This unique quartz cell employs a large diameter (8mm) and a short length (46mm) to guarantee self-flushing and no clogging after long-term deployment even in biologically active waters. Furthermore, an optional UV LED (280 nm), integrated into the conductivity cell, sterilizes the sample under measurement, thus avoiding the early growth of biofouling inside the quartz measuring cell.
DATA STORAGE AND BATTERY
The OS308 CTD is equipped with a 4Gbyte data memory, which allows the storing of about 250 millions data sets, each one being composed of the reading of all the installed sensors plus the acquisition date and time. Different types of battery can be installed in the CTD housing. The battery endurance is considerably extended, because the OS308 enters a deep sleep mode between acquisitions and drains only 4μAh from the battery. For instance, by monitoring every hour, the OS308 (CTD only) can run for about 9 years on a single Lithium size “C” cell.
SELF-RECORDING MODES
•Continuous: Sampling at configurable rates: up to 22 Hz. Multiple cycles can be obtained by switching the CTD ON/OFF.
•Pressure: Data is sampled at pressure intervals. Multiple profiles can be obtained by switching the CTD ON/OFF.
•Timed: CTD collects a series of samples and then sleeps for the configured time interval (5s up to 1 day).
•Conditional: Data acquisition is started and continues while the reading from a selected sensor is above the threshold value. Monitoring of the selected sensor threshold value can be configured to occur at intervals (between 5s and 1 day).
•Burst: Burst sampling carried out at configured time intervals (5s up to 1 day).
AUV INTEGRATION
Automatic, real-time data transmission compatible with: Bluefin and OEX AUVs are available, together with a proprietary data transmission format. To further reduce weight and size a shorter housing is available upon request.
SOFTWARE
Idronaut software allow the operator to configure the OS308 data acquisition, logger functions and upload data from the memory. They are:
• WTERM: Windows Terminal emulation software to easily communicate with the OS308 using the built-in operator interface and communication protocol. Users are easily able to view real time data, configure the probe for unattended acquisition and upload stored data.
• REDAS-5: Windows Data processing and retrieval software, which allows the display and plotting of conductivity, temperature, pressure and derived variables such as salinity, sound speed and water density, according to UNESCO formulas and recommendations.
