Valeport MIDAS CTD
The MIDAS CTD (previously known as the Model 606) is Valeport’s premier Conductivity, Depth and Temperature unit (CDT) Profiler. High accuracy sensors and robust titanium design allow reliable operation to 5000m depth, under the harshest conditions. It also features truly synchronised sampling to ensure that all sensors are sampled at exactly the same point during a profile.
Description
The MIDAS CTD is fitted with Valeport’s low external field conductivity sensor, a fast response PRT temperature sensor, and a high accuracy strain gauge pressure transducer.
The MIDAS CTD uses the concept of distributed processing, where each sensor has its own microprocessor controlling sampling and calibration of readings. Each of these is then controlled by a central processor, which issues global commands and handles all the data. This means that all data is sampled at precisely the same instant, giving superior quality profile data.
The instrument will operate autonomously, with setup and data extraction performed by direct communications with PC before and after deployment. It also operates in real time, with a choice of communication protocols for a variety of cable lengths, all fitted as standard and selected by pin choice on the output connector.
The MIDAS CTD is fitted with 8Mb solid state non-volatile FLASH memory. Total capacity depends on sampling mode; continuous & burst modes have a single time stamp at the start of the file, trip mode (profiling) stores a time stamp with each reading. A single line of CTD data uses 6bytes, and a time stamp uses 7 bytes. Continuous: >1,350,000 data points Profile: >600,000 data points (53 profiles to 6000m).
System supplied with DataLog 400 Windows based PC software, for instrument setup, data extraction and display. DataLog 400 is licence free.
Primarily for use as as live recording profiler, the MIDAS CTD also has a range of communications options for real time use, and the low power consumption and large memory also make it suitable for longer term deployments.
Technical information
The MIDAS CTD is fitted with Valeport’s high stability conductivity
sensor, a high accuracy temperature compensated piezoresistive pressure transducer,
and a fast response PRT temperature sensor
Conductivity
Range: 0 – 80 mS/cm
Resolution: 0.002mS/cm
Accuracy: ±0.01mS/cm
Temperature
Range: -5°C to +35°C
Resolution: 0.005°C
Accuracy: ±0.01°C
Pressure
Range: 10, 50, 100, 300 or 600bar
Resolution: 0.001% range
Accuracy: ±0.01% range
