LI-COR LI-830, Руководство пользователя

Страница: 40 / 50

Appendix A. Equation Summary
A-21
Spanning H
2
O (LI-850 only)
When the command for setting the span for H
2
O is received, along with the target
concentration W
T
, from the target concentration, the target absoprtance
α
T
is com-
puted from
A-22
LI-850 computes S
w0
from equation A-23 , where is averaged over five seconds.
A-23
where
A-24
The instrument retains the following values, which are used for subsequent sec-
ondary spans:
A-25
Secondary Span H
2
O (LI-850 only)
When the secondary span command for H
2
O is received, the instrument computes
new values for both S
w0
and S
w1
. First, it measures a new and computes a new
from equation A-24. Then, it uses these plus the retained values ( and
from the previous normal span) to compute
A-26
Given the new span slope S
w1
, it updates the span offset S
w0
by equation A-23.
A-6 Using the LI-830 and LI-850 Gas Analyzers