Understanding the certificate of calibration
Constant
. Each sensor has a slightly different output at a
given radiation intensity and will therefore have a unique
Calibration Constant
. The LI-250A measures the current out-
put of the sensor (microamps) and converts the measured
current to units of radiation.
Understanding the certificate of calibration
The Certificate of Calibration (provided with each light
sensor,
not
the LI-250A) includes the model and serial
number of the sensor, the date of manufacture, the date
of the most recent calibration, and calibration factors that
are suitable for a variety of applications. Calibration cer-
tificates are available from
The
Calibration Constant
is the relationship between a
microamp of sensor current output and photons of radi-
ation. The value is labeled
Output
on the calibration sheet.
The value labeled
For use with LI-COR handheld meters and
loggers:
is the negative reciprocal of the calibration con-
stant (Multiplier = -1 / Calibration Constant).
This is the
value you will enter in the LI-250A
.
Since the Calibration Constant is unique for each sensor,
it must be entered into the LI-250A each time the sensor is
changed or recalibrated. For the LI-192SA and LI-193SA
Underwater Quantum Sensors, there are two calibration
multipliers (see
on page 8); one for "in air" oper-
ation and one for "in water" operation. Use the multiplier
that is appropriate for your application.
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