DEFI series loggers are accurate, compact, and light weight data loggers to be used in various conditions.
Infrared communication with the interface, and high-speed USB communication with a PC. DEFI series offers the following data loggers: temperature, light intensity, and pressure, which can be used in a variety of observations.
Pocket-size conductivity and temperature recorder
DEFI2-CT is an accurate conductivity and temperature sensor. The sensor consists in a “7-electrode conductivity sensor” with an integrated temperature sensor. The temperature sensor is very stable and consists of a fast response and highly reliable thermistor. The conductivity sensor has both ends of the conductivity cell ending with same polarity, which results in no electric current flowing through the external side of the sensor and eliminates external influence. The compact design, with infra-red communication and titanium pressure-resistant case ensures a robust structure resistant to corrosion and humidity, which allows the instrument to be deployed in a variety of sites and conditions.
Pocket-size temperature logger
High-precision pocket size water temperature logger for long-term observations. (maximum of 573 days for 1 minute interval observation). The reduced size of the DEFI2-T allows the device to be installed in large numbers in a single mooring system, allowing investigating temperature fluctuations at increased spatial resolution.
Also, AAA alkaline batteries used for DEFI2-T are locally available around the world, reducing the operating costs.
Pocket-size PAR logger
High-precision pocket-size light intensity logger for long-term observations. (maximum 573 days for 1 minute interval observation). The cosine correction allows the sensor to have an excellent spectral sensitivity even when the light source is not directly above the sensor.
Also, AAA alkaline batteries used for DEFI2-L are locally available around the world, reducing the operating costs.
* We recommend measuring light quantum in air as well as underwater.
Pocket-size pressure logger
DEFI2-DHG and DEFI2-D
High-precision pocket-size pressure logger(depth meter) for long-term observations. DEFI2-DHG and DEFI2-D are pocket-size pressure loggers (depth meters) are suitable for long-term observations (maximum of 573 days and 52 days respectively with 1 minute interval observation).
These two loggers can be used attached to fishing nets, underwater instruments and moorings. AAA alkaline batteries used for DEFI2-D and DEFI2-DHG are locally available around the world, reducing the operating costs.
*In order to measure sea level fluctuations, we recommend the installation of one unit for atmospheric pressure monitoring (atmospheric pressure compensation).
DEFI Series common interface. DEFI series interface communicates with a common personal computer.