Kett FD-720, Руководство по эксплуатации

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Bias
Bias is used to change the average lower limit of fixed values with respect to predicted measure-
ment values. On the FD-720, a bias of anywhere from –9.99 to +9.99 percent may be specified.
When performing a comparative measurement, the FD-720 automatically requests a bias to be
used to correct measurements to match those obtained in automatic halting mode.
Comparative measuring mode
In comparative measuring mode, predicted measurements are displayed while measuring is in
progress and measuring is halted under the same conditions as when operating in automatic
halting mode. The difference between the measured value and predicted value is displayed as the
bias.
In order to obtain more accurate predicted measurements, it is recommended that when calculat-
ing the bias you should perform at least 5 comparative measurements and take the average of all
measurements obtained to use as the bias.
You should also take care in terms of the amount of material and the way the sample material is
placed onto the sample dish to ensure that the sample material is laid out as evenly as possible
and sample amounts are similar.
Note that no predicted measurement or bias can be calculated if a predicted measurement is not
obtained before the measurement is completed.
Predictive measuring mode
It is possible to obtain actual predicted measurements by specifying the same drying temperature,
predicted value convergence range, and bias as calculated when performing comparative mea-
surements in comparative measuring mode.
Note that measuring is halted if no predicted measurement has been calculated after 30 minutes
have elapsed since the time when the measurement was begun.