Great Plains YP1630F-1670 Material Rate - Manual (Page 21)

Great Plains Manufacturing, Inc. Contents Appendix Fertilizer Rate 19
2012-12-04 Contents Appendix 401-832B
Fertilizer Meter Calibration
The rate charts are based on 11-52-0 dry fertilizer with a
density of 0.96 kg/liter (60 pounds per cubic foot).
Material of a different density will meter at a
proportionately different rate. Heavier material has a
higher rate for the same setting. Lighter has a lower rate
for the same setting.
Material with a different particle shape or cohesion may
meter at a slightly different rate, even if the density
matches the charts.
Great Plains strongly recommends calibrating for the
exact material you intend to apply. Adjusting first for
density may allow the calibration to arrive at your desired
rate with fewer samples.
Density Adjustment
If your material density differs from the chart value by
more than a few percent, pick a different initial chart rate,
on an inverse proportion basis:
Figure 11
Gearbox and Calibration Crank
34498
1
3
2
Example Density Adjustment:
Desired FieldRate : 104 kg/ha
Default chart gearbox setting: 43
Material ChartDensity : 0.96 kg/l
Actual material FieldDensity : 1.2 kg/l
Density ratio: 0.80 = 0.96 ÷ 1.2
AdjustedRate : 83.2 = 104
× 0.80
Start with the settings for a rate of 83.2.
Nearest chart rate is: 85.2
Adjusted initial gearbox setting: 39
AdjustedRate FieldRate
ChartDensity
FieldDensity
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