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Ultrasonic Ping Module. Range.

Hi All,

I tried to find information about the real distance measurement of the ultrasonic module HC-RS04 but without success.

In the description it is written that range is 0-4.5m (0-5m in another source) but in reality I can only measure the distance up to 2.5m

Does anybody know anything about it?

Is it okay for those crapy sensors from e-bay?

Thank you guys in advance!


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Did you buy one of those sensors of ebay or are you considering getting one? 


I bought one of those! Actually I bought two of them :) 

And both of them are the same.

Do you think I made a mistake? ;)

Well that is what I am wondering, I am tempted to get 2 or 3 myself. But before I would like to see somebody here on LMR get one working with an Arduino.

Still 2 meters isn’t too bad, 4.5 or 5 would have been nice though.

You might want to post your code and setup so that people can help you.

Do you mean HC-SR04 not HC-RS04?,

If so I bought one and it works fine with arduino.


Range is well over 3 meters.

Yeah, I meant HC-SR04

The one that looks like this :)


And I used the algorithm from here http://iteadstudio.com/application-note/arduino-ultrasonic-ranging-with-hc-sr04/

However I couldn't get the range more than 2.5 metre :(