Water Quality Sensors

Hydrolab LDO

The Hydrolab LDO Sensor is a high accuracy optical sensor designed to deliver reliable dissolved oxygen measurements for professional water quality monitoring applications.  Using advanced luminescent dissolved oxygen (LDO) technology, the sensor provides stable, drift resistant performance without the frequent maintenance requirements of traditional membrane based DO sensors.

Factory integrated into the Hydrolab HL4 and HL7 multiparameter water quality meters, this LDO sensor is ideal for environmental monitoring, research, and long-term field deployments where dependable data and minimal maintenance are essential.  Its optical design ensures consistent performance across a wide range of aquatic environments, including rivers, lakes, estuaries, and groundwater systems.

SENSOR COMPATIBILITY

The Hydrolab LDO Sensor is factory integrated into the following Hydrolab water quality meters:

• Hydrolab HL4
• Hydrolab HL7

Factory integration ensures optimal sensor alignment, reliable communication with the sonde, and accurate compensation using integrated temperature and pressure data.

SENSOR SPECIFICATIONS

Parameters Measured
• Dissolved Oxygen (mg/L & %Sat)

Range
0 – 60 mg/L

Accuracy
+/- 0.1 mg/L at <8 mg/L
+/- 0.2 mg/L at >8 mg/L
+/- 10% reading >20 mg/L

Resolution
0.01 mg/L

ADVANTAGES OF OPTICAL (LDO) TECHNOLOGY

Unlike traditional electrochemical DO sensors, the Hydrolab LDO Sensor does not consume oxygen during measurement and does not require soft membranes or electrolyte solutions.  This results in:

• Reduced maintenance requirements
• Improved long-term stability
• Faster setup and calibration
• Reliable performance in low flow and stagnant water conditions

These advantages make the Hydrolab LDO sensor particularly well suited to unattended deployments and remote monitoring applications.

WHY DISSOLVED OXYGEN IS CRITICAL

Dissolved oxygen is one of the most important indicators of aquatic ecosystem health. Accurate DO measurements are essential for assessing water quality, identifying pollution events, monitoring biological activity, and ensuring regulatory compliance.  The Hydrolab Dissolved Oxygen sensor delivers confidence in both spot measurements and continuous monitoring scenarios, helping users make informed decisions based on reliable data.

IMPORTANT

Note: The Hydrolab LDO Sensor is supplied as a factory-integrated accessory and cannot be purchased as a standalone product.

The Hydrolab HL4 and HL7 water quality meters are manufactured by Hydrolab and proudly represented by Aqualab Scientific.