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FastCAT CTD Sensor
SBE 49

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Print version     Current manual (older manuals)     Reference Sheet     Configuration options & accessories

SBE 49 FastCAT CTD Sensor



The SBE 49 FastCAT is an integrated CTD sensor intended for use as a modular component in towed vehicles, ROVs, AUVs, or other autonomous platforms that can supply DC power and acquire serial data. FastCAT’s pump-controlled / TC-ducted flow feature minimizes salinity spiking, and its 16 Hz sampling provides very high spatial resolution of oceanographic structures and gradients.

FastCAT’s temperature thermistor and conductivity cell are the same as used in our premium 911plus CTD system. The strain-gauge pressure sensor is offered in eight full scale ranges from 20 to 7000 dbars. Sophisticated interface circuitry provides very high resolution and accuracy.

FastCAT is an easy-to-use, light, and compact instrument ruggedly made of titanium and other low-maintenance (plastic) materials; it is well suited to even the smallest vehicle. There are straightforward commands for continuous (full rate or averaged) or single sample acquisition. EEPROM-stored calibration coefficients permit data output in ASCII engineering units (degrees C, Siemens/m, decibars, Salinity [PSU], and sound velocity [m/sec]), or the user can select raw data output if desired.

FastCAT must be externally powered, and its RS-232C data logged or telemetered by the vehicle to which it is mounted. As FastCAT does not support auxiliary sensors, where such sensors are required the user's vehicle must be equipped to acquire their signals independently.


FastCAT has two sampling modes:


A standard FastCAT is supplied with:

FastCAT options include:


FastCAT is supplied with a powerful Win 2000/XP software package, Seasoft©  V2. Seasoft's modular programs include:


  Measurement Range Initial Accuracy Typical Stability Resolution Calibration
0 - 9 ± 0.0003 0.0003 per month 0.00005 (oceanic waters; resolves 0.4 ppm in salinity)

0.00007 (high salinity waters; resolves 0.4 ppm in salinity)

0.00001 (fresh waters; resolves 0.1 ppm in salinity)

0 to 9 S/m;
physical calibration over 2.6 to 6 S/m, plus zero conductivity (air)
-5 to +35 ± 0.002 0.0002 per month 0.0001 +1 to +32
Pressure 0 to 20 / 100 / 350 / 600 /  1000 / 2000 / 3500 / 7000 meters ± 0.1% of full scale range 0.05% of full scale range per year 0.002% of full scale range Ambient to full scale range in 5 steps

Power Requirements:
Input power 0.75 Amps at 9-24 VDC
Turn-on transient 750 mA
Sampling and transmitting (includes pump)
   350 mA at 9V
   285 mA at 12V
   180 mA at 19V

Housing Material and Depth Rating:
Standard  3AL/2.5V Titanium, 7000 meters (22,900 feet)
Optional  Plastic, 350 meters (1150 feet)

Standard titanium housing
   In air 
2.7 kg (6 lbs)
   In water  1.4 kg (3 lbs)
Optional plastic housing
   In air  1.8 kg (4 lbs)
   In water  0.5 kg (1 lb)

Connector (Standard XSG-4-BCL-HP-SS; optional MCBH-4MP (WB), TI [3/8 inch length base, 1/2-20 thread]):


Documentation -- manual, photos, technical papers, application notes, etc.

Sales Information -- options, accessories, cables, mount kits, spares, etc.

Software -- components of Seasoft V2

Links to Other Instruments of Interest

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Specifications are subject to change without notice.

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