Measure screed residual moisture correctly with Trotec BM31

Hello,

for measuring the residual moisture, I bought the Trotec BM31. Unfortunately, I am unsure about the interpretation of the displayed value, whether I can start laying the vinyl. The display shows 48 digits.

I have attached the excerpt from the instruction manual. On the scale, 48 = dry.

But what do the values below in the table mean?

It would be great if someone could help me.

Thank you very much.

These are comparative values from measuring devices that make them reasonable and meaningful.

As the manufacturer of your device already says:

Pre-testing the suitability of building materials for CM measurements.

Unfortunately, your value should really only be seen as an indicator (e.g., whether it is worth carrying out the CM measurement).

And the device is not calibrated either.

Only with a proper CM measurement do you perform a depth measurement in the screed, and also the sample quantity (50g to 100g) makes the result meaningful.

From my point of view, the only thing you can do with this thing is to determine that in one place or another, the surface is drier or wetter in comparison. Nothing more.

I also purchased the device to roughly assess the residual moisture of the screed. This works well....we are currently at the peak of the screed program and at about 60 digits in the light areas. Unfortunately, we also have many sintering spots in our anhydrite screed...in these, the value is still over 80!

This is already worrying me because grinding will only be done when the tiler arrives...which doesn't really make much sense since not much will probably change at the sintering spots until then, right?