Vaisala HMK15, Руководство пользователя

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Chapter 4 ________________ Instructions for the Calibration of Humidity Instruments
VAISALA _________________________________________________________ 19
CHAPTER 4
INSTRUCTIONS FOR THE
CALIBRATION OF HUMIDITY
INSTRUMENTS
General Instructions
Usually, the errors during humidity calibration are due to
temperature differences. A temperature difference of ±1 °C
at +20 °C between the air in the chamber and the sensor
causes an error of ±3 %RH at 50 %RH and an error of
±6 %RH at 97 %RH. The more the transportation or process
temperatures differ from the temperature at the calibration
site, the longer the stabilization time required. In laboratory
use, the calibrator should be stored in that part of the room
where the temperature is most stable. The calibrator must be
kept out of direct sunlight and away from localized heat
sources, such as spot lights, heaters and soldering irons. If
the probe/transmitter is checked against several humidity
references, the checking must first be made at the dry end.
More detailed instructions are given in individual manuals
of transmitters and probes.
Handle the probe as little as possible. Do not hold the salt
chamber or other parts of the calibrator in hand during
calibration as they warm up and cause errors in the readings.