LI-COR LI-6400, Manual

Page: 266 / 846

Data Logging
AutoProgram Descriptions
9-22 Using the LI-6400
9
which allows you to enter a CO
2
differential threshold that will cause match-
ing to occur if the absolute value of the sample - reference IRGA is smaller.
If you wanted to match automatically on every observation, enter a large
number (100, 1000, etc.). If you never want to match automatically during the
AutoProgram, enter 0. Typically, you might want to use 15 or 20 µmol mol
-1
as the threshold.
If matching occurs (for either software version), it occurs immediately after
the minimum wait time. Following automatic matching (which typically
takes about 30 seconds), there will be a short delay (10 seconds), then the
maximum wait time and stability checking is entered. Thus, automatic match-
ing tends to increase the total time between logging events by about 40 sec-
onds.
Two Styles for ÒProgramÓ
The Program field (Figure 9-16 on page 9-20) has two styles with the A-Ci-
Curve AutoProgram (and also LightCurve ). The delimiter used is a semico-
lon, or asterisk, as explained in Table 9-4.
ÒAutoLogÓ
AutoLog is designed to log instantaneous data at regular intervals. (If you
need data faster than every 2 or 3 seconds, then you should use
Buffered AutoLog instead).
■ ■
■ ■
AutoLog prompts for the following:
1 Log every __ secs:
Enter the desired period between logged observations.
2 Add __ observations:
This determines how many observations AutoLog should record. If you man-
ually log data while AutoLog is running, it does not affect when AutoLog
quits.
Table 9-4. Delimiters used in the Program field for A-CiCurve and LightCurve .
Style Meaning
00;01;30 (In minimum wait time) 1 minute 30 seconds remains until
the program starts checking for stability to see if it can log
data.
00*01*30 (Checking stability) As soon as the stability meets the cri-
terion, it will log. Otherwise, logging will occur in 1
minute and 30 seconds.