Sea & Sun Technology CTD48Mc

The CTD48Mc probe is a very small and handy microprocessor controlled multiparameter memory probe for precise measurements as well as for self-contained operation in deep and shallow water with up to 4 sensors and a maximum depth down to 2000 m. It measures conductivity, temperature, pressure and one optional parameter.
The difference between the CTD48Mc and the previous version of CTD48 Probe are:

• low weight
• powerful micro controller
• calibration coefficients stored inside the probe
• output of calculated / physical data
• powerful interfaces
• rechargeable batteries (NO opening of the probe!)

The CTD48Mc can work in different modes. One mode is standard SST mode, as with all previous SST probes. In this mode, the data can be read, graphed and saved via an SST programme.
In another mode, physical and calculated data, such as salinity, density or speed of sound, can be readout directly as readable characters (ASCII).
The probe can be operated in the following environments:

Online operation
During measurements, the probe must be connected by a cable to a device for displaying and recording measured values. The PC with the “SDA” software application represents the device for displaying and recording measured values in this case. The probe transmits the measured values to this connected data acquisition unit, i.e. the probe does not store any measurement data in its internal data memory. Power is supplied by the internal battery or from an external source.

The online operation is implemented by the following operation mode:

• RS-232 (factory default)
• USB UART (factory default – for configuration and memory readout)
• Ethernet (10/100 Mbit/s)

Memory operation
The probe can perform measurements automatically and save measurement results internally. Using a configuration cable, a software application transmits to the probe from a PC the settings that control the probe in memory operation. During the actual measurement, no connection is required between the probe and the control unit. In memory operation, the electrical supply is gener¬ally provided by the internal batteries; alternatively, power supply via a connection cable is possible. After measurement, the internally stored measured values are transmitted to a device for storage and display. In this case, the PC running the “SDA” software application is the device con¬figuring the probe and displaying and storing the measured values. The probe can also transfer the currently measured values to a device for display or storage during memory operation and using a connecting cable.

The memory operation is divided into the following operation modes:

• Continuous mode: each data set is stored.
• Time mode: data sets are only stored at programmable intervals with several selectable schemes.
• Increment mode: data sets are stored at programmable depth stamps.

The CTD48Mc is equipped with an 8 channel data acquisition system with 20 bit resolution. High long-term stability and automatic self-calibration of analogue digital converter guarantee stable and precise CTD measurements for many years.

The probe power supply of the is activated by touching a reed contact with a magnetic rod. LED displays power supply status and optical control of memory access.

The supplied Standard Data Acquisition Software package “SST-SDA” includes the handling of the logging process and the display of online or recorded data with a shared graphic user interface.

Standard models:
CTD48Mc:
Online and memory probe for measurement of conductivity, pressure, temperature + 1 optional sensor

Standard sensors:

• Conductivity (С)
• Temperature (T)
• Pressure (D)

Additional sensors:

• Oxygen
• Turbidity
• pH
• Redox (OPR)
• Flourometer

Calculated parameters:

• salinity
• sound velocity
• Kappa 25 mS/cm (electric conductivity)
• sigma – t (potential density of a fluid)