Vaisala HUMICAP DMT132, Руководство пользователя

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> ct
T 22.3104 Ref1 ? 22.3
Press any key when ready ...
T 44.9746 Ref2 ?
45
OK
>
4.9.3 Adjust Capacitance Measurement
Use the
CRH
command to perform a one-point or two-point correction to the capacitance
measurement of the transmitter. This command changes the offset and gain of the
measured capacitance, and therefore affects humidity measurement over the entire
temperature range.
This command should be used only when the HUMICAP â sensor has been
replaced, or the measurement has drifted significantly. For normal adjustment, use the
RHCAL command instead.
CAUTION!
CRH <cr>
When performing a one-point adjustment, you need to place the transmitter in a single
humidity reference with RH < 50%. Run the command and enter the exact RH of the
reference after the measurement has stabilized. Exit the command by pressing the ESC key
before proceeding to the second point (see the first example below).
For two-point adjustment, the first point requires a RH < 50% humidity reference, the
second point must be RH > 50%. There must also be at least 30 percentage points of
difference between the references. The measurement reading for the second point will
appear when this requirement is met.
Example: one-point adjustment
> crh
RH: 11.41200712 Ref1 ? 11.3
Press any key when ready
OK
>
Example: two-point adjustment
Chapter 4 – Operation
41