Aanderaa 4531 Oxygen Optode Sensors
Features
- Optical lifetime-based luminescence quenching measurement principle
- Long time stability with red reference LED
- Available with integrated cable or wet-mate connector termination
- Expedited repair and warranty service
- Lifetime technical support
- More
Overview
The Aanderaa Oxygen Optodes are based on the ability of selected substances to act as dynamic fluorescence quenchers. The fluorescent indicator is a special platinum porphyrin complex embedded in a gas-permeable foil that is exposed to the surrounding water. The sensor has an incorporated temperature thermistor, which enables linearization and temperature compensation of the phase measurements to provide the absolute O2 concentration.
Mechanics
A black optical isolation coating protects the complex from sunlight and fluorescent particles in the water. This sensing foil is mounted on a glass window, providing optical sampling from inside a watertight housing. The sensing foil is excited by modulated blue light; the sensor measures the phase of the returned red light. For improved stability, the optode also performs a reference phase reading using a red LED that does not produce fluorescence in the foil.
Ranges
The Oxygen Optode outputs data in RS-232 and analog 0-5V, 0-10V or 4-20mA. The sensor can present the O2 concentration in µM, Air Saturation in % and Temperature in °C.
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