Vaisala MMT162 - Manual (Page 53)

Chapter 6 ___________________________________________________ Calibration and Adjustment
VAISALA _______________________________________________________________________ 51
CHAPTER 6
CALIBRATION AND ADJUSTMENT
This chapter provides information that is needed in calibration and
adjustment of the product.
The MMT162 is fully calibrated and adjusted as shipped from factory.
The calibration interval depends on the application. It is recommended
that calibration is done always when there is a reason to believe that the
device is not within the accuracy specifications.
You can calibrate the MMT162 yourself or send it to Vaisala for
calibration. Calibration and adjustment is usually carried out through
serial line. One-point calibrations and adjustments can also be done by
using an MI70 indicator and Vaisala humidity calibrator HMK15.
Before the calibration, the used sensor needs to be cleaned with
instrument air to blow out existing oil or gently first flush with hepthane
(C
7
H
16
) and dry with instrument air to decrease response time, see
section Cleaning on page 47.
NOTE It is important to clean the sensor before calibration as the oily
sensor can contaminate the salt bath and change the reference
condition.
Vaisala HUMICAP ® hand-held moisture and temperature in oil meter
MM70 can also be used for calibration.