HydroCAT CTD Documentation

Knowledge Base

Sea-Bird Scientific HydroCAT CTD X-Series Integration Guide


The Sea-Bird Scientific HydroCAT CTD measures conductivity, temperature, pressure, and optical dissolved oxygen. It easily integrates with NexSens X-Series data loggers using the SDI-12 sensor interface.

An illustration of a Sea-Bird Scientific HydroCAT CTD connected to a NexSens X3 Data Logger transmitting data to the cloud, which is shown on the WQData LIVE mobile app (depicted on a phone).

Sensor Setup

Before the sensor can be deployed, it must first be set up through Sea-Bird Scientific UCI software. Follow the manufacturer’s guidelines for sensor setup and set the operating mode to SDI-12.

Note: Be sure to note the parameter list, as this will be needed to align with selected parameters in the logger.

 

Connecting with X-Series Loggers

Next, the HydroCAT will need to be connected to the X-Series logger through CONNECT software. If you have not yet done so, set up the project in WQData LIVE.

  1. Connect the sensor using the supplied cable to one of the open sensor ports on the logger and note the port number.
  2. Plug the X3 into the USB port of the computer and power it on with the AC power cable.
  3. Open CONNECT and select the SENSOR tab.
    Open CONNECT and select the SENSOR tab.
  4. Click Add and select Sea-Bird from the Manufacturer drop-down. Then select the appropriate model.
  5. Adjust the SDI-12 address if needed and select the port number.
  6. Select either Continuous or Switch in the Power drop-down.
    1. Switch is recommended.
  7. Add or remove sensor parameters as needed.
    Sea-Bird Scientific HydroCAT CTD sensor profile in NexSens CONNECT Software.
  8. Select Save Sensor Profile.
  9. Complete the setup for all other sensors, and then click Save.
  10. Name the Sensor Profile List and select Ok.
    Save Sensor Profile List.
  11. Complete system setup by clicking Deploy.
    CONNECT interface with an Sea-Bird Scientific HydroCAT CTD added.
  12. Confirm that data is being transferred to WQData LIVE at the next interval (default is 10 minutes).

 

Mounting

Deployment setups will vary based on the platform, application, and site location. For general buoy mounting instructions and pole-mount assembly, see below.

 

Buoy-Based Deployments

First, follow the appropriate User Guide in the Knowledge Base for buoy assembly. Then, use the NexSens HydroCAT CTD Instrument Cage Mount to attach the sensor to the buoy cage by following the steps below.

  1. Attach the mounting plate to the inside of the cage, keeping in mind that the sensor will face the surface of the water when deployed.
    Attach the mounting plate to the inside of the cage, keeping in mind that the sensor will face the surface of the water when deployed.
  2. Attach the sensor support brackets.
    Attach the sensor support brackets.
  3. Slide the silicon O-rings onto the HydroCAT sensor and adjust as needed to align with the support brackets.
    Slide the silicon O-rings onto the HydroCAT sensor and adjust as needed to align with the support brackets.
  4. Secure the sensor in place by screwing in the top brackets.
    Secure the sensor in place by screwing in the top brackets.
  5. Secure the sensor cable on the buoy cage, taking care to minimize strain.
    Secure the sensor cable on the buoy cage, taking care to minimize strain.

 

Near-Shore Deployments

The HydroCAT can be mounted to pilings, bridge piers or other shoreside structures. It’s best to design a sliding or removable mounting bracket to provide service access to the sensor above water.

The unit can be deployed inside a perforated pipe to protect it from debris, but it will need to be a tight fit or secured to avoid impact caused by waves and rough seas. Regular inspection and maintenance are required to remove fouling and ensure adequate water flow.

  1. Mount the bracket or pipe.
  2. Using the instrument cable, connect the sensor to the data logger while taking care to minimize cable strain.

Using the instrument cable, connect the sensor to the data logger while taking care to minimize cable strain.