Print version Current manual (older manuals) Reference Sheet Configuration options & accessories
for deployment in orientation shown (sensor end up) for proper operation.
The SBE 37-IMP-ODO MicroCAT is a high-accuracy conductivity and temperature (pressure optional) recorder with internal batteries, memory, built-in Inductive Modem, integral Pump, and Optical Dissolved Oxygen sensor. Constructed of titanium and other non-corroding materials for long life with minimal maintenance, the MicroCAT is designed for long duration deployments on moorings. Calibration coefficients are stored in EEPROM, allowing output of C, T, P, DO, and time in ASCII engineering units (raw output available).
The Inductive Modem (IM) system provides reliable, low-cost, real-time data transmission for up to 100 IM-enabled instruments using plastic-coated wire rope (typically 3 x 19 galvanized steel) as both the transmission line and mooring tension member. IM instruments clamp anywhere along the rugged mooring wire. Expensive and potentially unreliable multi-conductor electrical cables with fixed position underwater connectors are not required. IM moorings are easily reconfigured (positions changed or instruments added or removed), by sliding and re-clamping sensors on the cable. IM systems are much less expensive and more power-efficient than acoustic modems, and offer reliable communication over greater distances.
In a typical mooring, an Inductive Modem Module (IMM) or Surface Inductive Modem (SIM) housed in the buoy communicates with underwater IM instruments and is interfaced to a computer or data logger via an RS-232 serial port. The computer or data logger (not supplied by Sea-Bird) is programmed to poll each IM instrument on the mooring for its data, and send the data to a telemetry transmitter (satellite link, cell phone, RF modem, etc.). The MicroCAT saves data in memory for upload after recovery, providing a data backup if real-time telemetry is interrupted.
Conductivity and Temperature sensors are based on our field-proven SeaCAT and SeaCATplus. Electrical isolation of conductivity electronics eliminates any possibility of ground-loop noise. Our unique internal-field conductivity cell permits the use of expendable anti-foulant devices, for long-term bio-fouling protection. The aged and pressure-protected thermistor has a long history of exceptional accuracy and stability.
The oxygen sensor is our field-proven SBE 63 Optical Dissolved Oxygen sensor.
The optional strain-gauge pressure sensor is available in eight ranges, to a maximum depth of 7000 meters. Compensation of the temperature influence on pressure is performed by the MicroCAT's CPU.
The integral pump runs each time the MicroCAT samples, providing the following advantages:
With Adaptive Pump Control, the MicroCAT calculates the pumping time for best oxygen accuracy as a function of the previous sample's temperature and pressure (maximizing data quality while minimizing power consumption).
User-selectable operating modes include:
The MicroCAT is supplied with a powerful Windows software package, Seasoft© V2, which includes:
DATA STORAGE AND BATTERY ENDURANCE
Temperature and conductivity are stored 6 bytes/sample, time 4 bytes/sample, oxygen 6 bytes/sample, and optional pressure 5 bytes/sample; memory capacity is in excess of 380,000 samples (with pressure). The MicroCAT is powered by a 7.8 Amp-hour (nominal) battery pack consisting of twelve AA lithium cells (Saft LS14500) which, when removed from the MicroCAT, can be shipped via commercial aircraft. Battery endurance varies widely, depending on the sampling scheme and deployment pressure and temperature. Sampling every 10 minutes in water temperatures of approximately 10 °C, the MicroCAT can be deployed for almost 6 months (24,000 samples); see the manual for example calculations.
to 7 S/m
(0 to 70 mS/cm)
± 0.0003 S/m
|-5 to 45||
(-5 to 35 °C);
± 0.01 (35 to 45 °C)
|0.0002 per month||0.0001|
20 / 100 / 350 /
1000 / 2000 / 3500 / 7000 m
(meters of deployment depth capability)
|± 0.1% of full scale range||0.05% of full scale range per year||0.002% of full scale range|
120% of surface saturation in
natural waters (fresh and salt)
(equivalent to 0.07 ml/L or 0.1 mg/L)
1 µmol/kg/100,000 samples (20 °C)
Clock Stability: 5 seconds/month
Quiescent: 0.0007 Watts
CTD-DO Sample Acquisition
Without pressure 0.10 Watts
With pressure 0.17 Watts
CTD-DO Sample Waiting (not
sampling, pump running, excluding pump):
With pressure 0.016 Watts
Pump: 0.12 Watts
IM 0.009 Watts listening, 0.13 Watts transmitting
RS-232 0.06 Watts
Power Supply: 7.8 Amp-hour (nominal) battery pack
Housing, Depth Rating, & Weight:
|Housing Material||Depth Rating||Weight (with standard mounting clamp & guide)|
|Plastic||350 m (1150 ft)||In air 3.7 kg (8.3 lbs); in water 1.8 kg (4.0 lbs)|
|Titanium||7000 m (23,000 feet)||In air 4.4 kg (9.8 lbs); in water 2.5 kg (5.5 lbs)|
Note: 103 mm dimension is for plastic housing; titanium housing dome is 9 mm smaller
ADDITIONAL INFORMATION / LINKS:
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
Specifications are subject to change without notice.
Sea-Bird Home Phone: (+1) 425-643-9866 E-mail: firstname.lastname@example.org