Vaisala MGP261, Руководство пользователя

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2. Select > Calibrate > Yes .
3. Select one of the adjustment options in the Calibrate menu and see the separate
instructions for each option.
8.2.1 Example: 2-Point Adjustment with Zero Point Adjustment
When making a 2-point adjustment, the low end adjustment is carried out simultaneously for
all measurement parameters by adjusting the zero point signal in the
Zero point adjustment
tab.
This means that, instead of carrying out a 2-point adjustment for each measurement
parameter separately using a low end and a high end reference, the low end adjustment of all
measurement parameters is replaced with the zero point adjustment. After making the zero
point adjustment, you only need to adjust the high end measurement of each measurement
parameter when making a 2-point adjustment.
Example procedure outline for 2-point adjustment of CH
4
and CO
2
using nitrogen as the 0%
reference ( Zero point adjustment ) and a 60 % CH
4
/ 40 % CO
2
gas mixture as the reference
for the second adjustment points:
1. Zero point adjustment tab: adjust the zero signal (low end reference point, 0 %) for both
CH
4
and CO
2
using nitrogen.
2. CH₄ adjustment tab: adjust the high end reference point (60 %) for CH
4
using the CH
4
-
CO
2
mixture.
3. CH₄ adjustment tab: activate the CH
4
adjustment.
4. CO₂ adjustment tab: adjust the high end reference point (40 %) for CO
2
using the CH
4
-
CO
2
mixture.
5. CO₂ adjustment tab : activate the CO
2
adjustment.
8.2.2 Zero Point Adjustment
The zero point adjustment adjusts the zero output signal of the probe and applies
simultaneously to all gas measurement parameters (CH
4
, CO
2
, and H
2
O,). This means that,
instead of carrying out a 2-point adjustment for each gas measurement parameter separately
using a low end and high end reference, the low end adjustment of all gas measurement
parameters is replaced with the zero point adjustment.
After carrying out the zero point adjustment, you only need to adjust the high end
measurement of each gas measurement parameter when carrying out a 2-point adjustment.
Always use nitrogen as the reference gas for the zero point adjustment.
Chapter 8 – Calibration
53