T-Chain (Temperature String)
Monitor Temperature, Dissolved Oxygen, Pressure and PAR in your lake.

The T-Chain is used as a water quality monitoring and lake management device that collects water column temperature, dissolved oxygen, PAR and pressure measurements. T-Chains are currently being used to monitor lake and reservoir thermocline and stratification, detect dissolved oxyen fluctuations, observe internal waves, collect data under ice, discover plumes, observe upwelling and eddies, record lake turnover and more. The T-Chain is also used in marine environments.

The T-Chain can collect data as rapidly as once per second along a customer specified node location cable. This temperature string (T-Chain) is unique due to its very high temperature accuracy and rapid response to temperature variations. It often finds application in connection with numerical model validations as well as routine monitoring.

The temperature string (T-Chain) consists of a single polyurethane sheathed cable with a Kevlar core. This cable carries digital-format data from the various sensors. Temperature sensors are permanently molded onto the cable but dissolved oxygen and pressure sensors are attached via underwater connectors. The number and type of sensors, length of cable, and other parameters are defined by the customer subject to the temperature string design rules. Each chain is custom assembled depending upon the customer's specific requirements.

PME can supply the T-Chain to be connected to a variety of Campbell Scientific data loggers.

• Sensors
• Data Logger
• Documents
• Research

Temperature Sensors: Produce detailed thermal data that can be used to determine water stratification, mixing, internal tides, and more. More


Oxygen Sensors: Produce dissolved oxygen data within the water column by measuring lifetime-based luminescence quenching of fluorescence of a thin membrane. More


Pressure Sensor: A strain-gage transducer used to measure water depth. This sensor is an absolute pressure sensor and is available in three pressure ranges. More


PAR Sensor: A Li-Cor LI-192SA Underwater Quantum Sensor that measures Photosynthetic Photon Flux Density. More

The T-Chain is connected to a Campbell Scientific data logger through the RS-232 port.

Compatible Campbell Scientific Data Loggers


CR800-Series Measurement and Control Dataloggers



CR1000 Measurement and Control System



CR3000 Micrologger

T-Chain Data Sheet

T-Chain Design Guidelines

T-Chain off Scripps Pier: The Coastal Observing Research Development Center at Scripps Institution of Oceanography maintains a PME temperature chain at their research pier as part of an ocean observing program.


Monitoring Mixing Dynamics and Water Quality at Toolik Lake: Researchers are monitoring the thermal stratification and mixing dynamics in order to look at the movement of nutrient flux