Trouble shooting method of turbidity sensor of water quality analyzer

We all know that water quality analysis equipment will often have problems if it is not calibrated, but if the same is not done in accordance with the regulations during the calibration time, it is easy to show problems, such as negative values u200bu200bwhen calibrating turbidity, and other error prompts. Therefore, if we want to calibrate a turbidity water quality instrument, we must understand the corresponding treatment methods when there is a problem. For this reason, we have summarized the troubleshooting methods for the turbidity sensor of the water quality analysis instrument.

The sensors of turbidity water quality analyzers are generally more well-used. The use of appropriate storage and protection methods in daily life can help extend the service life of the sensor. But if there is an error message during the calibration of the turbidity sensor, please check the following:

1. Ensure that the turbidity calibration solution has not expired and ensure its quality.

2. The calibration environment (such as calibration cups, sensor shields, and sensors) should be kept outstanding. If there is a problem with negative turbidity readings, please refer to the application note.

3. There should be no reflective materials on the sensor shield and calibration cup. There should be no scratches on the bottom of the metal sensor shield (inside; facing the sensor).

4. If you suspect port contamination, please remove the sensor and follow the instructions in the section on cleaning the sensor port.

How to prevent the turbidity sensor from reading negative?

Generally, the negative reading of the turbidity sensor is always correlated with the calibration value during calibration. Although we strictly follow the calibration process to perform, sometimes it is impossible to clean the sensor, the calibration cup, and the sensor guard to the level of the calibration value. Even in a laboratory environment, brand-new instruments will exhibit 0-0.1 FNU contamination. The used turbidity sensor may be close to 1.0 FNU after cleaning.

So when we encounter this situation, we can use the method of setting the calibration value to avoid it. For example, for example, we generally enter a calibration value of 0, but in practice, the reading is mostly 0.6 FNU. If the turbidity of the calibration environment is If it is 0.3 FNU, the reading of the water quality analyzer is likely to show a measured value of -0.3 FNU.

So when we calibrate the sensor of the turbidity water quality analysis instrument, in addition to preventing the pollution of the sensor itself and the calibration tool, we must also specify the calibration value. Generally, we recommend that we set the calibration value from 0 to 1 FNU.

The following tips can help eliminate negative turbidity readings:

1. Use the calibration cup and sensor guard dedicated to calibration. The calibration cup and sensor protection equipment are easily contaminated with the passage of time, especially when the water quality samples measured by the instrument are poor or are analyzed on-site.

2. The pollution degree of the zero turbidity standard is very small when the instrument is properly cleaned and protected. The average pollutant level ranges from 0.2 to 0.8 NTU. Knowing this, you can select a number (0.5) between these points and enter it as the first calibration point.

3. It is best to calibrate turbidity in a laboratory environment; on-site calibration may lead to erroneous readings.