PSI PlantPen/N-Pen N 110, Instruction Manual

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5 G
ETTING STARTED
Define the number of samples per each experimental group. The measurement is performed as a series of measurements, where the
number of measurements can be set in range from 6 to 20. The pre-set number 10 can be used, for example, to measure 10 plants (each
plant is measured once) or to measure 5 plants (each plant is measured twice). In case of high variability, the user is advised to reconsider
the sampling method or to increase the sampling scale.
The N-Pen is controlled using two buttons:
•
Use the MENU key to scroll through sequential menu options on the digital display.
•
Use the SET key to select a menu option based on cursor (>) position.
5.1 C
ALIBRATION
Calibration assures you that your measurements are accurate within the specification limits that led you to select the instrument in the
first place. It is better to calibrate your device before every set of samples. For Calibration of N-Pen use white reflectance standard.
Before calibration, make sure that the optical part of the device, including the inner part of the sample holder, is
clean.
It is necessary to calibrate N-Pen after every switch ON.
Prior measurement perform the calibration as follows:
•
For calibration use white reflectance standard (It is part of leaf clip)
•
Turn ON device – hold SET button for 1 sec.
•
Close the leaf clip (white standard is on bottom part of the leaf clip)
•
Go to Calibration ( “Insert white sample” appears on display)
•
Press SET button to confirm the calibration and wait until the calibration step is completed.
•
Calibration is automatically stored into the device memory.
•
The device is now ready to measure other samples.
5.2 M
EASUREMENT
Please follow these instructions to perform a measurement:
•
Select Measurement in the main menu and select the type of crop (i.e. wheat, barley or corn). Then select the type of prediction,
which is either N-content in dry matter of plant , or the postharvest grain N-content. When ready, the display shows the number
of remaining measurements, for instance “Meas. left: 10“. You can change the pre -set number in Settings > Readings .
•
Select the second or the third youngest leaf and clip the leaf in the mid part along the leaf axis to the detector chamber.
•
Start the measurement by pressing SET to obtain and store the readings. The display shows the number of remaining measurements
when ready for the next measurement.
•
Repeat the previous step to complete the whole series of measurement.
•
When complete, the instrument displays NDGI index value and the nitrogen prediction.
•
During the measurement all data are stored into the device memory.