Overview

The OPD700 Dissolved Oxygen Sensor supports one-point calibration and two-point calibration. One-point calibration is 100% full-scale calibration. Usually, one-point calibration can meet most usage requirements. Adding zero-point calibration on the basis of 100% saturation calibration is two-point calibration. If the measured dissolved oxygen concentration is relatively low, a two-point calibration is required to obtain more accurate data.

One-point calibration method?

1. Water-saturated air calibration

This is a relatively simple and fast 100% calibration method. prepare a beaker or bottle, put distilled water in it, and place the sensor vertically about 2cm above the water surface. At this time, above the water surface in an environment of 100% air humidity, the saturation of dissolved oxygen is 100%, so it can be used as a dissolved oxygen sensor full-scale calibration environment.

If the conditions on site are limited and time is tight, you can even place the Dissolved Oxygen Probe directly in the air for full calibration. When using the air calibration method, be careful not to touch the temperature sensor at the end of the sensor with your hands, otherwise it will cause inaccurate temperature and affect the calibration accuracy. Wait for the value to stabilize before starting calibration.

Note that when calibrating in air, there should be no water droplets on the membrane cover of the sensor.

Zero-point calibration method

Zero point calibration needs to be performed on the basis of 100% calibration completion. We need to prepare oxygen-free water. Dissolve 50g of anhydrous sodium sulfite in 1000mL of distilled water and stri until completely dissolved.

Put the DO Sensor into oxygen-free water, and note that the temperature sensor at the tail should also be completely immersed in the water. Wait for the value to stabilize and start zero point calibration.
After the calibration is completed, immediately use clean water to rinse the residual sodium sulfite solution on the surface of the sensor before putting it into use or storage.
Do not let the dissoloved oxygen sensor soak in oxygen-free water for a long time, otherwise the membrane cover will be damaged.

Delfino focuses on the research and development and production of water quality analysis instruments. Its main products include pH ORP analyzer, conductivity analyzer, turbidity analyzer, COD analyzer, dissolved oxygen analyzer, ammonium analyzer, chlorine analyzer, etc.Our company provides matching online dissolved oxygen controllers for calibration, and also provides computer software for calibration. Users can also use their computer software for calibration. Users can also use their own modbus software for calibration. For specific operation details, please contact sales staff.