Calibration of dissolved oxygen by fluorimetry in air

Writer： admin Time：2023-02-01 10:09:48 Browse：493℃

Appliances and raw materials required

Anhydrous sodium sulfite powder

Distilled water or deionized water (Watsons distilled Water)

Beakers, gloves, stirring rod, air pump

Calibration Solution Preparation

Preparation for 100% oxygen environment: Prepare 1 beaker, take 200mL purified water(or distilled water) and pour it into the cup, add to the air pump, and fully aerate the solution(at least 30 minutes).

Note: If the field conditions really do not allow, the sensor can be directly put into the air(calibration accuracy will be slightly deviated).

Calibration (take 2-point calibration as an example)

Restore user calibration data by default, K=1, B=0(see modbus documentation for details).

Take the sensor out of the zero oxygen, wipe the sensor measurement end face with a paper towel, put the sensor into 100% environment (air), read the value of dissolved oxygen, wait for the data to stabilize, the value is close to 1 (Saturation is 100%), and record the value as Y.

Place the sensor in the prepared zero-point solution, immerse the front end of the sensor completely in the solution, read the value of dissolved oxygen, and wait for the data to stabilize, with the value approaching 0.01 (Saturation is 1%), for example Dissolved oxygen = 0.015, recorded as X.

Record K and B values according to the following formula:K=(1-0)/(Y-X), B= - KX

Write K, B values to the sensor.

(See modBus documentation)

Yosemitech Sensor has also developed pc-based calibration software for Y504 dissolved oxygen sensor. You only need to connect the probe to the calibration software through the computer interface, and you can easily complete the calibration of the sensor according to the software prompts.