METER ACCUPAR LP-80, Manual

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LP-80
4. SERVICE
This section describes the calibration and maintenance of the LP-80. Troubleshooting
solutions and customer service information are also provided.
4.1 CALIBRATION
The LP-80 calibrates its sensors against the external PAR sensor ( Section 3.2.2 ). However, as
is the case with all electronic components, the external sensor sensitivity will shift over time.
As a result, METER recommends sending the external sensor to METER for recalibration. For
external PAR sensors that are used heavily, annual calibration is recommended. For periodic
use, one recalibration every 2 to 3 years should be adequate.
METER recommends calibrating the LP-80 to the external PAR sensor at least once per hour
to maintain a stable calibration between the two sensors.
Use the following steps to calibrate the LP-80 to the external PAR sensor.
1. Unscrew the bolt from the external PAR sensor.
2. Place the external PAR sensor above the hole in the bubble level of the LP-80.
3. Insert the bolt through the hole in the LP-80 from back to front and screw into the
external PAR sensor until hand-tight ( Figure 29 ).
Figure 29 Level the probe
4. Level the probe and sensor in an unshaded area ( Figure 30 ).
NOTE: The LP-80 can also be calibrated on a flat board or platform propped at an angle to get more direct
sunlight.