Vaisala AQT530, Руководство по настройке

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3. To check the setting, type:
show time
More information
‣
Setting date (date command) (page 30)
4.6 Adjusting linear correction
Span and zero values are used for the linear correction of the measured values. Zero
parameter corrects the offset and span the sensitivity (gain).
You can set the zero and span correction for gas and particle measurements.
The adjusted values affect the measured values of the following Modbus register addresses.
To adjust the span and zero through the Modbus interface, use registers 0x0086 - 0x0097.
Table 14 Modbus registers for measurement data
Address Description
0x0000 - 0x0006 Gas concentrations in parts per billion (ppb) with linear correction
0x0066 - 0x006B
Gas concentrations in μg/m
3
with linear correction
0x0008 - 0x0009
0x0037
Particle matter PM
1
, PM
2.5
, and PM
10
in μg/m
3
with linear correction
After making these changes, AQT530 outputs data corrected by these zero and span
correction factors.
Table 15 Linear correction parameters - gases
Parameter Type Range Default Unit Description
co_zero
int16 −10000 ... 10000 0 ppb CO sensor zero
correction
co_span
uint8 1 ... 255 100 0.01 CO sensor span
correction (1 ... 255 =
0.01 ... 2.55)
no_zero
int16 −10000 ... 10000 0 ppb NO sensor zero
correction
no_span
uint8 1 ... 255 100 0.01 NO sensor span
correction (1 ... 255 =
0.01 ... 2.55)
no2_zero
int16 −10000 ... 10000 0 ppb NO
2
sensor zero
correction
Chapter 4 – CLI operation
25