There is information on ultrasonic level gauges
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I heard from a colleague that when using an ultrasonic level gauge with process media that have a lot of foam on the surface, it can cause measurement errors. May I ask whether such errors result in the displayed level being higher or lower than the actual level? What is the theoretical basis?
Yes, the reason is that foam affects its echo; as for the level of the liquid, it’s hard to say – it depends on where the reflection point is
What if the reflection point is right in the middle of the foam? What would happen if the reflection point were near the foam? Thank you for participating!
The estimate is likely to be high, as the reflected waves come from the foam above the liquid surface.
It should be on the high side, as all reflection points are above the liquid surface; if it’s confirmed that the gauge is not damaged, then the lowest point should represent the actual liquid level. This is for reference only!
It should be on the high side, because the foam floats on top of the liquid, so the reflection point is higher than the actual liquid level
On the high side! The foam always remains suspended on the surface of the liquid; when it comes into contact with the radar and generates echoes, this can affect the actual liquid level! Multiple waveforms are displayed on the radar chart. I guess you shouldn’t have chosen a radar level gauge for that application in the first place! Or is the level accuracy not high enough for you? But even if high precision isn’t required, there’s no need to choose such an expensive level gauge!
On the high side! The positions of all points on the foam must be above the liquid level, thereby reducing the reflection time. This in turn causes the displayed liquid level to be higher than actual
If there is a lot of foam in the liquid, I suggest installing a wave guide, which will give good results