Conductivity meter miniature, salinity, temperature sensor and depth logger
Model DST CTD
DST CTD is the smallest salinity logger on the market that measures and records salinity (conductivity), temperature and depth. Recorded data is stored in the logger‘s internal memory with a real-time clock reference for each measurement.
The DST CTD is supported by the SeaStar software and the Communication Box which serves as an interface between the logger and a PC. Communication between the logger and the Communication Box is wireless.In SeaStar, the user sets the start time, start date and sampling interval before starting the recorder. Up to seven different intervals can be set for the same measurement sequence. This is especially useful when more frequent measurements are needed at a certain time period. One interval for the whole measurement sequence is more commonly used though.
After recovering the DST data logger, recorded data is uploaded to SeaStar where results are displayed both in graphic and tabular form. After retrieving the data, the logger can be re-programmed and reused as long as the battery lasts.A set of Communication Box and SeaStar software needs to be purchased with the first order.
Star-Oddi offers a plastic protective housing for use under harsh environmental conditions and for mounting to buoys, deploymnet lines, moorings or underwater gear. For fish tagging projects Star-Oddi can provide a special tag holder kit for fastening the DST externally on fish.
|Features on request|
|The optional logic feature allows users to choose a depth limit where the logger starts and stops recording. The logger is not storing measurements while outside the predetermined depth, saving memory and battery life. The user can choose in the SeaStar software at what depth limit the recordings should start at. This can be especially useful when used on fishing gear, or on animals that spend their time both in and out of water.|
|Examples of application|
The DST CTD is suitable for various studies:
We offer three conductivity ranges:
You can calculate the most suitable conductivity range for your study with the free SalCalc conductivity calculator software.
Conductivity is a combination of salinity and temperature. The DST CTD is basically a conductivity recorder from which the salinity is calculated. To view the graphical display of the connection between conductivity, salinity and temperature for each conductivity type, click on the type names above.
The variation of salinity range and accuracy unit value with temperature can be seen for each type below:
|Sensors||Conductivity (salinity), temperature, pressure|
|Size (diameter x length)||15mm x 46mm|
|Housing material||Alumina (Ceramic)|
|Weight (in air/in water)||
in air: 21g
in water: 13g
|Memory type||Non-volatile EEPROM|
|Memory capacity||87,217 measurements per sensor|
|Memory capacity bytes||392,478 bytes / conductivity-temperature-depth 4.5 bytes|
|Memory management||Custom programming|
|Data resolution||12 bits|
|Temperature resolution||0.032°C (0.058°F)|
|Temperature accuracy||+/-0.1°C (0.18°F)|
|Temperature range||-1°C to +40°C (30°F to 104°F)|
|Temperature response time||Time constant (63%) reached in 20 sec.|
|Standard depth ranges||1m-100m , 5m-500m , 5m-1200m, 10m-2000m|
|Depth resolution||0.03% of selected range|
|Depth accuracy||+/-0.4% of selected range for 100m to 500m range, +/-0.6% of selected range for 1200m to 2000m range|
|Depth response time||Immediate|
Available ranges (customer specified):
1) 3 to 37 mS/cm
2) 13 to 50 mS/cm
3) 0.3 to 5 mS/cm
|Conductivity resolution||0.01 mS/cm (average)|
|Conductivity accuracy||+/-1.5 mS/cm|
|Salinity range||Depends on conductivity and temperature range|
|Salinity resolution||0.02 PSU (average)|
|Salinity accuracy||+/-1 (PSU)*|
|Data retention||25 years|
Real time clock
Accuracy +/-1 min/month
|Sampling interval||In second(s), minute(s) or hour(s)|
Number of different
|1 to 7 within same measurement sequence|
|Communications||Communication Box, RS-232C 9 pin serial or USB|
|Attachment hole||0.9 mm (in diameter)|
|Battery life||4 years**|
* Based on conductivity full scale accuracy at 24°C
** For sampling interval of 10 minutes; salinity, temperature and pressure recorded simultaneously.
Specifications may change without notice.