Suitable for rapid profiling down to 6000m depth, the MIDAS SVP gives the most accurate Sound Velocity Profiles currently possible.
Replacing Valeport’s renowned Model 650 Mk2 Sound Velocity Profiler, it features titanium construction and a large memory. As well as using the world leading digital time of flight sound speed sensor, the instrument has a ±0.01% pressure sensor, and features Valeport’s synchronised sampling technique to guarantee that all sensors are sampled at exactly the same point during a profile.
The MIDAS SVP is fitted with Valeport’s digital time of flight sound velocity sensor, a high accuracy temperature compensated piezo-resistive pressure transducer, and a fast response PRT temperature sensor.
1375 – 1900m/s
-5°C to +35°C
10, 50, 100, 300 or 600bar
The MIDAS SVP 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.
Regular output from all sensors at 1, 2, 4 or 8Hz
Regular sampling pattern, where instrument takes a number of readings, then sleeps for a defined time.
Data is output as a chosen parameter changes by a set value, usually Pressure for profiling.
Instrument sleeps until a selected parameter reaches a set value.
Instrument sleeps until predefined start time
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:
Up to 200m cable, direct to serial port via USB adaptor
Up to 1000m cable, addressable half duplex comms
2 wire power & comms up to 6000m of cable (cable dependant)
2400 - 115200 (FSK fixed at 19200, USB 460800)
8 data bits, 1 stop bit, No parity, No flow control
The MIDAS SVP is fitted with 16Mb 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 SVP data uses 8 bytes, and a time stamp uses 7 bytes.