One-point offset and gain calibrations, Hmi41 as a reference meter – Vaisala Calibration of Digital Transmitters with HMI41 User Manual

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Chapter 3 _______________________________________________________________ Calibration

VAISALA _______________________________________________________________________ 15

One-Point Offset and Gain
Calibrations

Select the desired calibration with buttons ▲ and ▼. Select offset
calibration if the humidity is < 65%RH and gain calibration if the
humidity is > 65%RH:

Press ENTER to acknowledge the selection. A text similar to the
following appears on the display:

In following chapters, you will find instructions for performing offset
and gain calibrations in two different ways.

HMI41 as a Reference Meter

The HMI41 reference probe is used to show the correct humidity
value. Connect the cable and wait for the transmitter and reference
probe readings to stabilize; when both readings are stable, press
ENTER to conclude the calibration. When ENTER is pressed, the
transmitter reading is corrected to the HMI41 reference probe reading.

Numbers on the first line indicate the RH measured by the transmitter,
and numbers on the second line indicate the RH measured by the
reference probe. Let the readings stabilize.