Hach LDO™ (Dissolved Oxygen)

Since 2002, Hach has established itself as the premier provider of Luminescent Dissolved Oxygen technology, and only Hydrolab Series 5 sondes feature Hach LDO technology – designed, manufactured, and supported by Hach in Loveland, Colorado.

How the Hach LDO sensor works:

The Hach LDO sensor cap is coated with a luminescent material. Blue Light from an LED strikes the luminescent chemical on the sensor. The luminescent chemical instantly becomes excited. As the excited chemical relaxes, it releases red light. The higher the oxygen concentration, the less red light given off by the sensor cap. The red light is detected by a photo diode. The time it takes for the chemical to return to a relaxed state is measured.

The oxygen concentration is inversely proportional to the time it takes for the luminescent material on the sensor cap to return to a relaxed state.

Between flashes from the Blue LED, a red LED of known intensity is flashed. The red LED acts as an internal standard for reference comparison to the red light given off by the luminescent sensor cap. This comparison allows the sensor readings to remain stable for long periods of time.

Features:

• No membranes
• Calibrations that last
• Superior accuracy
• Compact housing allow complete integration into any sonde – DS5X, DS5, or even MS5

Benefits:

• Calibrations that last without drift means that deployments will last longer, reducing frequency of trips to the field for maintenance, saving you time and money
• No membranes so concerns about air bubbles, 24-hour membrane relaxation, and the art of maintenance are a thing of the past
• Does not consume oxygen so passive fouling will not affect DO readings
• Best accuracy because solid, defendable data is the ultimate goal
• Designed, manufactured, and supported by Hach Environmental, the experts in LDO technology, so all your questions can be addressed locally

Product Data:

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