Marine Measurements
CTD Products
  Citadel CTD-EK Digital
  Citadel CTD-EK Analog
  Citadel CTD-ES
  Citadel CTD-NH
  Citadel CTD-NV
  Citadel TS-N
  Citadel CT-ETH
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Marine Measurements

Teledyne RDI Citadel CTDs

Teledyne RDI Citadel CTDs  

After years as a Doppler manufacturer, we've stepped outside of our core technology via the introduction of our Citadel CTD (Conductivity, Temperature, and Depth) product line.

This product line delivers exciting and proven technology that is complementary to Teledyne RDI's ADCP products, and represents a tremendous opportunity to expand our product offerings and deliver turn-key solutions to our worldwide customer base.

CTDs are used extensively around the globe for the measurement of temperature and salinity, but also for the important derived parameters of density and speed of sound. They are used for academic, commercial and defense applications; and are often used in concert with ADCPs to gain a clearer understanding of the ocean's complex physical environment.

The Citadel family of CTDs includes the following products:

  Citadel CTD-NH:
Internal Field CTD for moored subsurface remote data collection
  Citadel TS-NH:
Thermosalinograph CTD for vessel-mounted data collection
  Citadel CTD-ES:
External field CTD for moving real-time and remote data collection
  Citadel CTD-NH   Citadel TS-NH   Citadel CTD-ES  
  Bio-fouling resistant, high-accuracy conductivity, temperature, and depth with external input, direct digital output, and datalogging capability
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  Thermosalinograph for surface salinity with in-line sensors
» more
  Compact Conductivity, Temperature and Depth meter with direct digital output
» more
OEM Solutions
  Citadel CTD-EK Digital:
External field CTD OEM kit with and without housing for real time data collection
  Citadel CTD-EK Analog:
External field CTD OEM kit with and without housing for real time data collection
    Citadel CTD-EK Digital   Citadel CTD-EK Analog  
    Conductivity and Temperature sensors with digital output for integration into user systems
» more
  Conductivity and Temperature Sensors with Analog Output for Integration into User Systems
» more
  Citadel CTD-NV:
Internal Field CTD for profiling real-time data collection
  Citadel CT-ETH:
Incorporates proven inductively coupled conductivity sensor technology with a thermistor
  Not sure which CTD is right for your application?

Click on our CTD Product Selection Guide.

CTD Product Selection Guide

Or, contact a member of our sales team to discuss your current application:

Tel: +1-858-842-2600
  Citadel CTD-NV   Citadel CT-ETH    
  Scientific-quality conductivity, temperature, and depth measurement capability utilizing patented Non-external Inductive Cell (NXIC) technology
» more
  Compact Conductivity and Temperature Meter with Direct Digital Output
» more

Integrated Solution!

Integrated Solution   Integrated Solution   Our Citadel CTD has been interfaced with our Workhorse ADCP, providing our customers with the ability to measure both physical and chemical properties via a single deployment
» Get the details

How and where are Citadel CTDs used?

CT/CTD Methods of Deployment   CT/CTD Methods of Deployment:

A Moored
Conductivity, Temperature and (optionally) Depth (CTD) sensors mounted on surface/subsurface buoys or mooring lines at multiple depths in the water column for time series measurements at a single location.

B Vessel Underway
CTD sensors mounted on moving surface vessels (research, ferry, container ship, etc) using a ducted flow-through system for measurement of surface temperature and salinity.

C Underwater Vehicles
CTD sensors mounted on sub-surface vessels (AUV, ROV, glider, etc) for measurement of temperature and salinity.

CT/CTD Applications:

1 Environmental Monitoring
Routine Conductivity, Temperature and (optionally) Depth (CTD) measurements for model inputs, outfall monitoring and environmental impact assessments from fixed stations.

2 Fisheries
CTD measurements to support biological studies including: habitat mapping, marine protected area programs, and fisheries stock assessment.

3 Hydrographic Surveys
Speed of Sound measurements to support bathymetry measurements.

4 Ocean Observing Networks
CTD measurements to support long-term monitoring in coastal observation networks.

5 Climate Change Research
CTD measurements to support calculations of the density and temperature in the ocean for global heat conveyor and climate change studies.

6 Remote Surveys
CTD measurements to support ocean models and world ocean circulation studies.

How is my data displayed?

How is my data displayed?   Each Citadel CTD product is shipped with a software package that allows you to easily test, configure, calculate power consumption, and deploy your Citadel CTD. After recovering your instrument, this same software package allows you to download your data, and provides a “quick view” to confirm your data integrity. Detailed data processing is just a few clicks away. This same package can export the data in a variety of formats, including one suitable for our post-processing package, which can filter the data, adjust the lags, and create publication-quality graphics.

Have an application you'd like to share?
We'd love to hear from you! (And, as a token of our appreciation, we'll send you a special gift!)
Please fill in this brief online form; and e-mail any accompanying photos or data sets to
Short on time? Contact Margo to schedule a quick telephone interview.