Great Plains VARIABLE RATE KIT Operator Manual - Manual (Page 18)

18 Air Drill Variable Rate Kit Front Parts Great Plains Mfg., Inc.
166-263M Front Parts 6/23/2010
Calibrate
Calibrate Speed Sensor
88. Perform a Calibrate Ground Speed.
Calibrate Material
Perform a calibration. The procedure is similar to that for
crank-set operations.
89. Consult the Seed Rate manual (167-085B) for (the
approximate) manually-set rate for your material.
90. Check that final Range gear pairing is the same on:
• the chart,
• the meter, and
• the Meter gear Range in the Channel Setup.
91. Enter the calibration screen.
At this time, the linear actuator becomes active. The
scale indicator moves to approximately mid-scale,
then stops.
Pointing to a specific value is not required, but
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 target rate, or at least to
within the 30
°-95° range.
92. Manually crank the meter for at least the number of
turns shown in the instruction of the Seed Rate
Manual for
1 ⁄
10
ha or
1 ⁄
10
ac.
The exact number of revolutions, cranking rate
b
,
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 the target rate, and for
1 ⁄
10
ha, you
establish a comfort level that the drill is set up cor-
rectly, in particular, that you are in the correct gear
Range for the desired application rate.
93. Weigh the dispensed material and enter it in the
menu. The monitor computes a Calibration Con-
stant for this material. Save this result.
b. If no “Variable Cal Const” was selected at step 84, crank at for most accurate results:
ADC2350/B, NTA907/3007HD: 2 to 2
1 ⁄
2
revolutions per second
NTA607/2007HD: 1 to 1
3 ⁄
4
revolutions per second
Example Calibration Screen:
Parameter Value Comment
CHANNEL 1 Example
material Wheat HRW Example
Density 60.0 LB/BU Example
Calibration
Constant
77591 PUL/FT From chart
Target Meter
rpm
20 RPM Example
# Meter
Revs
30 REV Example
Pulse Count 0 PUL Pre-Cal.
New Calib
Const
______ PUL/FT
Total #
Towers
5
Per Imple-
ment
Amount
Dispensed
______ LBS From Scale
Example:
ADC2350B cart and NTA3510 drill
Wheat, 2-star meter, single seed hopper in use
High Range at gearbox
Target rate of 133 kg/ha would be a scale setting of:
50
° (from Seed Rate manual charts)
A sample size of
1 ⁄
10
ha requires crank:
77 turns (from Seed Rate manual instructions)