LI-COR LI7200RS, Инструкция по эксплуатации

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(Data (Ndx 87665) (DiagVal 757) (Date 2009-09-10) (Time 14:06:44:140) CO2Raw
0.0332911) (H2ORaw 0.19299) (CO2D 5.20672) (H2OD 755.566) (Temp 15.517)
(Pres 99.4361)…
Data format without labels
87665 757 2009-09-10 14:06:44:140 0.0332911 0.19299 5.20672…
The End of Line Delimiters determine the character(s) that terminate the data
records. Depending on your recording device, a line feed, carriage return, or both
may be required to properly parse the data records.
Under Data Output, select the data records that you want to output; click
Select All
to choose all, or
Select None
to disable all checked values. The data items available
for display given in Table 3-1 on page 3-13.
DAC Configuration
The LI-7550 has the capability to output up to 6 variables on DAC channels 1-6.
The DACs page allows you to configure the DAC output channels by specifying
the source channel (e.g., CO
2
mmol/m
3
) that drives the analog signal, the source
channel value that corresponds to zero volts, and the source channel value that cor-
responds to full scale voltage (5V).
For example, to configure DAC #1 to output a voltage signal proportional to CO
2
mmol/m
3
, 20 mmol/m
3
full scale, select CO
2
mmol/m
3
under DAC1 'Source', and
set 0V = 0, and 5V = 20.
0V
→
0(X
o
, zero volts corresponds to 0 mmol/m
3
)
5V
→
20(X
F
, full scale corresponds to 20 mmol/m
3
)
When a voltage range R is selected, the DAC output voltage V resulting from a
CO
2
molar value X is given by
7-2
where R = 5V.
The DACs are linear, so in the example above, a measured voltage signal of 3 volts
would correspond to a CO
2
mmol/m
3
value of 12.
Section 7. Software Reference
7-15 DAC Configuration