OCEAN SEVEN 308 CTD
CTD LOGGER, VERY LOW POWER, SELF-RECORDING, PROFILING, MOORINGs, ROVs, AUVs ,ARCTIC, ANTARCTICA, BRINE,
The OCEAN SEVEN 308 CTD combines very high-quality electronics with exceptional sensors accuracy fulfilling the demand for a self-recording high performance CTD probe with very compact dimension and very low power consumption. This CTD can be easily integrated/adapted to third-party systems such us floating profilers and/or oceanographic moorings, ROVs and AUVs. IDRONAUT prides itself on the design of its full ocean depth, pump-free, low-maintenance sensor, central to which is the high accuracy seven-platinum-ring quartz conductivity cell. The self-flushing sensors makes this CTD ideal for fast profiling in a wide range of water types. The OS308 CTD standard interface is RS232C; other optional interfaces are: RS485 and wireless. The OS308 housing can be manufactured with either a 316 grade L stainless steel or titanium allowing deployment to depths of 1000 or 7000/10.000 dbar respectively.
IDRONAUT
BRUGHERIO (MB), IT
Description
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.
Temperature Sensor
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.
Data Storage and Battery
The OS308 CTD is equipped with a 4Gbyte data memory, which allows the storing of about 250 million 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.
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.
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).
- Sound Velocity Profiler: Data is sampled at pre-set pressure intervals and then exported .svp or .asvp format.
Specifications
-
General
-
Diameter [mm]
48
Housing Material
AISI316L or Titanium
Length [mm]
535
Max. cable length [m]
200
Weight in air [kg]
1
Year of initial development
2022
-
Observations
-
Min. time increment [s]
0
Min. depth increment [m]
0
-
Operation Characteristics
-
Display of analogue data
Y
Method of first recording
Internal memory
-
Pressure, temperature and conductivity sensor
-
Accuracy of temperature measurement
0.0015°C
Accuracy of conductivity measurement
0.00015 S/m
Accuracy of pressure sensor
0.05%FS
Conductivity sensor
Y
Max. conductivity [S/m]
9
Max. temperature [°C]
50
Min. temperature [°C]
-3
Pressure sensor
Y
Resolution of pressure [% FS]
0
Resolution of conductivity [10^-3 S/m]
0
Resolution of temperature [°C]
0
Temperature sensor
Y
Type of conductivity sensor
7-rings quartz cell
Type of pressure sensor
Transducer
Type of temperature sensor
Pt100
-
Software specifications
-
CTD Probe controller
Y
Graphical presentation
Y
Re-computation with raw data
Y
Raw data editing
Y
Software name
WTERM and REDAS-5
-
Environmental
-
Max. depth [m]
11
Max. pressure [bar]
1100
Operating temperature: min. [°C]
-5
-
Data and connectivity
-
Connectors
RS232
Dedicated sub-surface data logger
N
Dedicated surface data logger
N
Direct data reading
N
External recorder required
N
Internal memory
Y
Internal Memory [MB]
4000
Max. number of samples for self-recording [10^3]
25000
Telemetry link to remote location
N
Type of internal memory
SD card
-
Power
-
Battery
optional
Battery type
Lithium rechargeable, Alkaline unrechargeable
Battery duration [hr]
56
Max. operating power [V]
5
Min. operating power [V]
3
