Temperature Compensation; Auto-Hold Function; Measuring In Wood - Vwr Rm 20 Bedienungsanleitung

H63.0.21.6C-02_VWR
Water content w (= moisture relating to wet total mass)
water content [%] = ( (mass
or: water content [%] = (masse
The unit is % w.
Example: 1 kg wet wood that contains 500 g water has a water content of 50%

5.3 Temperature compensation

The temperature compensation is important for a reliable moisture-measuring.
There for the device features a automatic temperature compensation (Atc) or manual temperature compensation
input. The choice between the two possibilities is done in the Menu (Atc on/off)
According to the selected material characteristic curve the device will use the associated temperature compensation.
Calling temperature when using automatig temperature compensation (Atc on):
• press shortly
: in the display will appear: t.°C or t.°F and the temperature
• press
again to switch back to the measuring display.
Temperature selection:
• press shortly
: in the display will appear: t.°C or t.°F and the temperature
• set the temperature by pressing
• press
again to switch back to the measuring display.

5.4 Auto-Hold function

Particularly when measuring dry materials, electrostatic charges and other similar noise could dither the measuring
value. With activated auto-hold function the device will acquire an exact measuring value automatically. During that,
the device could be put down to avoid noise through discharge of the clothing etc.
After having acquired the measuring value, the display will change to 'HLD': The value will be frozen as long as a new
measuring is initiated by pressing key 3 (hold).

5.5 Measuring in wood

For measuring wood, punch in the measuring-pikes across to the wood-grain, having a good contact between the
pikes and the wood (measuring along wood-grain deviates minimal).
DO NOT HIT ONTO THE DEVICE OR PUNCH THE NEEDLES IN PEPPY
The device may be damaged.
Select correct wood-sort (see chapter 4.4 or Appendix A).
Ensure to have entered the correct temperature (see chapter 5.3).
Now read the measuring-value or when having activated the auto-hold-function initiate a new measuring by pressing
hold (key 3) .
The measured resistance will be extremely high when measuring dry wood (<15%) thus the measuring will need more
time to achieve its terminal value among other things static discharge could momentarily falsify the measuring.
Therefore beware of static discharge and wait long enough until a stable measuring value is displayed (unstable: „%"
blinking) or use the auto-hold-function (see chapter 5.4 Auto-Hold function).
When measuring very wet wood (e.g.>50%u) the measuring value may suffer from polarisation effects (steadily
decreasing measuring value). In this case the value 5 seconds after the insertion of the electrodes respectively after
switching on the instrument is valid.
Very accurate measures can be carried out within the range of 6 to 30%.
Beyond this range the accuracy will lessen, but the device will deliver reference values still sufficient for the
practitioner.
It is measured between the measuring-pikes insulated among each other. Requirements for an exact measurement:
- choose correct place to measure: place should be free of irregularities like resin–clusters, knurls, rifts, etc.
choose correct measure depth: Recommendation: for trimmed timber: punch in the pikes up to 1/3 of the material
-
thickness.
- Perform multiple measurements: the more measurements will be averaged, the more exact the result will be.
Pay attention to temperature-compensation: enter the exact temperature manually.
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Operating Manual RM 20
- mass ) / mass
wet dry wet
/ mass ) *100
water wet
or .
) *100
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