Dissoleved Oxygen Sensor

Measuring range: 0~20mg/L 0-100%

Dissoleved Oxygen Sensor



I. Working principle

The dissolved oxygen electrode is composed of a silver anode and a gold cathode. There is a potential difference of +800MV between the anode and the cathode. The cathode and anode are in the electrolyte solution and separated by a semipermeable membrane that only allows oxygen to pass through. Oxygen is reduced at the cathode through the following reaction, creating a point near the cathode where oxygen pressure is zero. Therefore, the current flowing through the two poles is converted into a voltage signal and the error due to temperature is compensated to calibrate the output and output the measurement to the data collector with appropriate results.

II. Specifications

Measuring range: 0~20mg/L 0-100%

III.Structure and function

  1. Connect to the datalogger through the Lightning interface, support front and back blind plugging, have hot-swappable function, and stable connection and transmission;
  2. Use a datalogger to connect to computers, mobile phones, tablets and other terminals through wired or wireless methods for data collection;
  3. The sensor supports common systems on the market, such as iOS, Android, windows systems, etc.

IV.Typical applications

This sensor can measure the concentration of dissolved oxygen in water samples in the field or in the laboratory. Dissolved oxygen is an important indicator of water quality, and various types of measurements can be made with this sensor:

  1. Monitor dissolved oxygen in fish tanks with aquatic animals and plants.
  2. Monitor changes in dissolved oxygen concentration caused by photosynthesis and respiration of aquatic plants.
  3. Conduct fixed-point monitoring of rivers or lakes to evaluate the impact of different types of animals and plants on water quality.
  4. Determine the relationship between dissolved oxygen concentration and temperature in water samples.


This product is suitable for educational use only and is not suitable for industrial, medical, research, or commercial applications.

VI.Usage Tips

    1. Warm up for 10 minutes before reading data.
    2. The sensor must be calibrated frequently, and the electrolyte solution also needs to be replaced. The time interval depends on the application frequency and measurement accuracy requirements.
    3. The semi-permeable membrane is relatively brittle and easily broken, so be careful during operation to prevent the permeable membrane cup from being punctured.
    4. Stir gently in the sample solution. NOTE: It is very important that the sensor maintains slight movement in the sample solution. To ensure that water flows through the top of the sensor during the measurement process. When the sensor measures dissolved oxygen, it extracts and separates the oxygen from the water. If the sensor is in stagnant water, the readings will gradually become smaller.
    5. When the sensor is not in use (for a short period of time), the probe should be soaked in clean water to prevent the electrolyte in the probe liquid chamber from drying up.
    6. After the experiment is completed, the probe of the dissolved oxygen sensor should be stored in a protective sleeve filled with water.
    7. Avoid contact with grease or other organic matter. Using the sensor in a non-aqueous solution or in a solution containing oil, grease, or attachments will shorten the life of the sensor.
    8. Dissolved oxygen sensor is used to measure the dissolved oxygen content in liquid.
    9. When using a dissolved oxygen sensor, the concentration of the solution to be measured should be made uniform first, otherwise the measurement results will be inaccurate.

    The probe life of the dissolved oxygen sensor is 2 years. Dissolved oxygen sensor probes can be ordered from our company.

    1. Response time: 95% of readings within 60 seconds.
    2. Temperature compensation range: 5-35℃.


Diaphragm replacement method

  1. Remove the pressure cap of the diaphragm from the sensor probe and pour out the original electrolyte.
  2. Take out the diaphragm from the supplied diaphragm bag, peel off one diaphragm from the protective paper, place it flat and press the pressure cap.