Envco – Environmental Equipment

Applications
The DST CTD can be used as a stand-alone logger for sampling in the oceans is also suitable for studies in e.g.:
• Marine animal tagging (externally)
• Oceanography
• Marine biology
• Ichtiology
• Hydrology
• Ecosystems research
Any other field where temperature, conductivity and pressure recording is required.

Logic Feature
Logic feature allows users to choose a depth limit where the logger starts and stops recording. The logger is in sleep mode while above the predetermined depth, saving memory and battery life. If the DST Logic unit is used in a logger all parameter measurements are taken at the same time – primary and secondary parameter settings are not possible. Logic feature is available for DST centi-T and DST centi-TD with extended memory (DST centi-ex), DST CTD and DST pitch & roll.

Temperature Calibration Outside Standard Range
Temperature calibration outside standard ranges or for smaller ranges is available for all products on request.

Technical Specification
Sensor Salinity (conductivity), temperature and depth*
Size 17mm x 46mm
Housing Material Alumina (Ceramic)
Weight in air: 21g in water: 13g
Batery Life 4 years**
Memory Type Non-volatile EEPROM
Memory Capacity 261,000 measurements DST in total ***
Memory Management Custom programming
Data Resolution 12 bits
Resolution Temperature 0.032°C (0.058°F)
Accuracy Temperature +/-0.1°C (0.18°F)
Temperature Range -1°C to +40°C (30°F to 104°F)
Response Time Temperature Time constant (63%) reached in 20 sec.
Standard Depth Ranges 100 m, 500 m, 1200 m
Resolution Depth 0.03% of full scale (FS)
Accuracy Depth +/-0.4% of selected range
Response Time Depth Immediate response
Conductivity Ranges Available ranges (customer specified): 1) 3 to 37 mS/cm 2) 10 to 50 mS/cm
Resolution Conductivity 0.015 mS/cm
Accuracy Conductivity +/-0.8 mS/cm
Salinity Range Depends on conductivity range selected
Resolution Salinity 0.02 PSU
Accuracy Salinity +/- 0.75 (PSU)
Data Retention 25 years
Clock Real time clock Accuracy +/-1 min/month
Sampling Interval In second(s), minute(s) or hour(s)
Number of different sampling intervals 1 to 7
Communications Communication Box, RS-232C 9 pin serial or USB
Attachment Hole 0.9 mm (in diameter)
Corrosive Resistance Oil, water, salt, antifreeze, brake fluid, diesel and gasoline

Additional Information *Pressure sensor optional **For sampling interval of 10 minutes; salinity, temperature and pressure recorded simultaneously. *** divided between 3 sensors for CTD and between 2 sensors for CT Specifications may change without notice.

A set of Communication Box and SeaStar software needs to be purchased with the first order. 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.

After recovering the DST recorded data is uploaded to SeaStar where results are displayed both in graphic and tabular form. After retrieving the data, the DST can be re-programmed and reused as long as the battery lasts.

Ordering Information
Conductivity (Salinity), Temperature and Depth (Pressure) Recorders
DST CTD Conductivity, temperature and depth recorder, memory: 87,000 recordings
DST CT Conductivity and temperature recorder, memory: 130,000 recordings

DST accessories
Com Box Communication box w/USB serial converter cable
SeaStar Graphic supporting software for Windows
Wire-L Wire fastener for the protective housings
Wire-F Wire fastener w/silicone pad for external fish tagging
Plate-P Hard plastic plate for external fish tagging
Fast-Kit Plastic holder plate with wires and a PE-plate

*Wireless Communication is not point to point. The logger does not need to be opened to communicate