Campbell Scientific LI190SB LI-COR Quantum Sensor - Manual (Page 14)

LI190SB Quantum Sensor
10: Average (P71)
1: 1
Reps
2: 3 Loc [ PAR_Den ]
11: If time is (P92)
1: 0
Minutes (Seconds --) into a
2: 1440 Interval (same units as above)
3: 10 Set Output Flag High (Flag 0)
12: Set Active Storage Area (P80)
1: 1
Final Storage Area 1
2: 102 Array ID
13: Real Time (P77)
1: 1220
Year,Day,Hour/Minute (midnight = 2400)
14: Resolution (P78)
1: 1
High Resolution
15: Totalize (P72)
1: 1
Reps
2: 4 Loc [ PAR_Tot ]
16: Resolution (P78)
1: 0
Low Resolution
5.3 Output Format Considerations
If solar radiation is totalized in units of mmoles m -2 , there is a possibility of
overranging the output limits. With the Edlog dataloggers (e.g. CR10X,
CR23X, CR510) the largest number that the datalogger can output to final
storage is 6999 in low resolution (default), and 99999 in high resolution.
The largest number that the datalogger can output is 6999 in low resolution
and 99999 in high resolution (Instruction 78, set resolution). If the
measurement value is totalized, there is some danger of overranging the output
limits, as shown in the following example.
EXAMPLE
Assume that daily total flux is desired, and the datalogger scan rate is 1 second.
With a multiplier that converts the readings to units of mmoles m
-2 and an
average PAR of 1 µmole s -1 m -2 , the maximum low resolution output limit will
be exceeded in less than 2 hours (6999 seconds).
Solution #1 - Record average flux density and later multiply the result by the
number of seconds in the output interval to arrive at total flux.
Solution #2 - Record total flux using the high resolution format. Another
alternative is to record total flux using the high resolution format. Instruction
78 is used to switch to the high resolution in the Edlog dataloggers. Use the
IEEE4 or Long data formats in the CR1000, CR5000, and CR9000
dataloggers. The disadvantage of the high resolution formats is that it takes
more memory per data point.
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