Robocraze HC-SR04 Ultrasonic Module Distance Measuring Sensor

Very nice and reliable product High accuracy rate of sensor and value for money and best durability

I purchased 2 qty of these modules for making a level sensor. I created an application to read the sensor data, convert it to distance and show it on PC COM Port. Initially, the sensor did not show any data and it was all zero's everytime. I checked the supply, signal connections and verified the software which was all good. After struggling for close to 3 hours, I figured out that the Trigger signal for the sensor is Active Low instead of Active High as suggested everywhere in forums and datasheets. As soon as I made the Trigger signal active Low, voila.... it started giving distance values which were almost close to real measurement. There was a deviation of about 2-4mm but it was Ok for my application. I was not able to install it and use it extensively now to check its long term stability, but initial reviews are good. PCB is of reasonable quality with nothing much to talk about. I am not clear on how to encapsulate this sensor in a sealed enclosure to avoid it from the vapors of the liquid I am planning to install with, since due to changes in ambient temperature, vapors will stick to the sensor grill in front thus reducing its accuracy and lifetime.

Working good

Excellent product

Not good

Works perfectly. Cheaper than other same products available &is thus good.

It's use only for Arduino board

Quite good accuracy was ok, but good