user63368: I was wondering if I connect a HC-SR04 to an Arduino or any other microcontroller by normal cables, what would be the maximum length of this cable so that the measurements will still be true, and not affected by the length of this cable?

user50183: The signal of an HC-SR04 is the pulse on the "Echo" wire. The length of that pulse is directly proportionate to the distance from the object.
Since cable length does not affect the duration of that pulse, measurement accuracy isn't affected either.

user26227: I have a couple measuring the liquid level of two tanks.
The units are distanced from the microcontroller by 12' of 18ga solid-core copper cable.
Testing was done with another microcontroller with the sensor attached by 6" cable to ensure accurate readings.
That's the longest I needed, so I haven't tested beyond that.

63368: <p>I was wondering if I connect a HC-SR04 to an Arduino or any other microcontroller by normal cables, what would be the maximum length of this cable so that the measurements will still be true, and not affected by the length of this cable?</p>
 50183: <p>The signal of an HC-SR04 is the pulse on the "Echo" wire. The length of that pulse is directly proportionate to the distance from the object.</p>

<p>Since cable length does not affect the duration of that pulse, measurement accuracy isn't affected either.</p>
 26227: <p>I have a couple measuring the liquid level of two tanks.</p>

<p>The units are distanced from the microcontroller by 12' of 18ga solid-core copper cable.</p>

<p>Testing was done with another microcontroller with the sensor attached by 6" cable to ensure accurate readings.</p>

<p>That's the longest I needed, so I haven't tested beyond that.</p>
