Kett AN-900, Руководство по эксплуатации

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6-4. BIAS Adjustment
With a rice-analysis device that applies Near-Infrared method like this unit, there are
times when the extended use of light-emitting parts, sensors, etc. experiences minor
changes that happen over time that can cause the measurement value to change.
The difference between AN-900 ’s measurement value and composition values of
standard samples (The known sample from the previous correct composition value)
is referred to as the bias. Refer to P26 concerning the possibility of accuracy checking
this according to the standard samples.
To adjust bias of the unit, there are two models manual or automatic.
To set unit manually, prepare several standard samples which should be different
values per each composition, performing measurement as usually several times.
And then calculate requested bias per composition by manual.
To set unit automatically, prepare one standard sample, and as you measure accord-
ing to display, the automatic bias adjustment should run smoothly.
Note : With the automatic adjustment, you need only one standard sample, so it is often convenience
to do, but you need to be careful of doing the adjustment incorrectly when making mistakes
with standard sample or doing other things to throw off the results.
(1) Protein CM Display (CM : Constant Moisture basis)
AN-900 ’s protein content shows the percentage contain in terms of whole grain, including mois-
ture. This altenative is convenient at times, when you are, for example, calculating the weight of
protein inside grain that was measured. But when you compare proteins among many different
moisture is contained, there are times when it is convenient to assume the fixed moisture content.
This consideration is “CM Protein” which is displayed as protein conversion by assuming the fixed
moisture content (with AN-900, this is the same as the “@ Moisture %” is specified). When the
fixed moisture content is assumed to be “ 0% ”, this is referred to as a “dry conversion” (DM : Dry
Moisture Basis)
The conversion formula is as follows, so if Protein, Moisture, and / or “@ Moisture %” are set
incorrectly, The “CM Protein” conversion value will not be displayed correctly.
Protein CM =
×
100 [%]
Protein
(100-Moisture) + @ Moisture %