Great Plains NTA3007 Operator Manual - Manual (Page 99)

Great Plains Manufacturing, Inc. Table of Contents Index Adjustments 95
2012-07-02 Table of Contents Index 166-371M
Variable Rate (Servo) Calibration
Note: For drills with manual (crank set) gearboxes, use
the instructions at“Calibration for Manual
Gearbox” on page 92.
Complete step 1 through step 13 beginning on page 90,
and “ACC Re-Configuration” from the Variable Rate
Kit manual 166-263M. You must have created or
selected a Material that matches the material you are
about to calibrate.
34. Check that final Range gear pairing is the same on:
• the chart,
• the meter, and
• the Meter gear Range in the Channel Setup.
35. Enter the calibration screen for the Channel
assigned to the meter to be calibrated.
At this time, the linear actuator for that meter’s
gearbox becomes active. The scale indicator moves
to approximately mid-scale, then stops.
Pointing to a specific value is not required, but it
needs to be in the range 30
° to 95°. Great Plains
recommends using a scale setting that is close to
your expected target rate.
Use the Inc+/Dec- softkeys on the monitor console to
adjust the indicator to the seed rate chart Gearbox
Setting value, or at least to within the 30
°-95° range.
36. Manually crank the meter for at least the number of
turns shown in the table at right for
1 ⁄
10
ha or
1 ⁄
10
ac.
The exact number of revolutions, cranking rate, and
precise starting and stopping handle angles are not
critical, as the system reads meter revolutions
accurately, and can compensate for shaft speed,
seed size and partial turns.
What matters is getting a large sample, to reduce
errors and increase confidence in the calibration.
Note: By calibrating at or near target rate, and for
1 ⁄
10
ha,
you establish a comfort level that the drill is set up
correctly, in particular, that you are in the correct
gear Range for the desired application rate.
Note: If no “Variable Cal Const” was selected during
material setup, crank no more than 2 revolutions
per second (120 rpm) for most accurate results.
Seeding Example; Initial Calibration Screen:
Servo Seeding Example
Calibration Targets:
Metric U.S. customary
Crop: Wheat Wheat
Flutes: 2 Stars 2 Stars
Target Seed Rate: 200 kg/ha 178 lbs/ac
Chart Data:
Range:
High High
Closest Chart Rate: 201.3 kg/ha 179.6 lbs/ac
Initial Variable Rate
Gearbox setting: 62 62
Initial Calibration
Constant: 79197 79197
Parameter Value Comment
CHANNEL 1 Example
Material Wheat HRW Example
Density 0.79 KG/L
61.4 LB/BU
Example
Calibration
Constant
77591
From chart
Target Meter
rpm
20 RPM
Example
# Meter
Revs
30 REV
Example
Pulse Count 0 PUL Pre-Cal.
New Calib
Const
______
Total #
Towers
4
Per Implement
Amount
Dispensed ______ KG
LB
From Scale
Calibration Crank Revolutions
NTA907 Contact Wheel
Revs/hectare 1050 1134
Per 1/10th ha 105 113
Jackshaft
NTA3007 Contact Wheel Jackshaft
Revs/acre 425 459
Per 1/10th ac 42.5 45.9