Hello together

Does anyone know if the A01NYUB ultrasonic sensor is temperature compensated? If I check the data compared with the temperature I've a very bad accuracy of the sensor what looks like the sensor does not use a compensation.

Is there a way to increase the accuracy? What is the used speed of sound for the calculation in the sensor?
Thanks for your feedback.

The sensor looks into a water tank and is wired to an ESP32 Firebeetle board. The Firebeetle board is located in a case combined with a solar cell mounted on a sunny location. The sensor itself is in the shadow. The Firebeetle measures the distance and the temperature inside the case every 30 minutes and logs the data to the cloud.

At ambient temperatures of 20 degrees the measurement is accurate but when the temperature goes down to 0 degree or up to 30 degree I see an error in the distance measurement what correlates with the measured temperature in the case.

I've tried to attach a diagram of the distance and the temperature measured over several days but it has not worked. I always get an upload error.
Hi, we checked it out.
Please check the environment elements as follows:
1. Please confirm the location of the product is now installed, the test of the object to the distance from the sensor. A small installation location, or a harsh environment, can cause the sensor to detect an incorrect output.

2. Please confirm that the object is stationary.
The accuracy defined by the sensor is the accuracy of the test at rest, and if the test is tested under movement or shaking, there may be an anomaly in the value.

3. Please compare the return value when the test object is stationary.
The error value at room temperature and the error value at the lowest temperature, and the error value at the highest temperature. The change in accuracy of the static test is reasonable in theory at 1-3cm, and the deviation is more than 10cm.

4. The product temperature compensation device is on the PCBA, sealed by the glue, with the outside temperature may be different.
Well with the advancement in technology now waterproof ultrasonic sensors are available but you have to keep a check on fake websites that sell fake products. I will prefer you to buy it from amazon as they are available there, Further, you can get papernow services to improve your skills. I just hope that the results turn out to be right. good luck!