Great Plains 3P806NT Material Rate - Manual (Page 46)

44 3P806NT Table of Contents Main Box Rates Great Plains Manufacturing, Inc.
151-143B Table of Contents Main Box Rates 2011-10-21
Metric Native Grass Rates
For U.S. customary units, see page 20.
Formulas Metric Example
Know your Desired seed rate in pounds per acre:
TargetRate Example target seed rate:
40 kg per hectare
Choose the number of rows to sample. Example:
3
Weigh the empty sample container(s):
ContainerWeight Example container are three 680 gram buckets:
2.04 kg
For a larger sample, we set the Drive Type high. Example starting calibration Drive Type:
2
As there is only minor benefit in changing the final drive
sprocket for calibration, we leave it as is. Example final drive sprocket:
20T
Examine the transmission for Standard vs. Seed Rate
Reduction/ Example transmission: Rate Reduction not installed:
Standard
Operate crank/gauge wheel for one tenth hectare:
CalibrationRevs Example:
162 revolutions (
1 ⁄
10
th
of 1622)
Weigh the collected seed plus container(s):
GrossWeight Example:
GrossWeight = 4.2 kg
Obtain the net sample weight: Example:
2.16 = 4.2 - 2.04, or:
NetSample = 2.16 kg
Determine the net sample weight per cup: Example:
2.16
÷ 3, or:
NetPerCup = 0.72 kg
Scale the sample to drill-wide: Example:
93.5 = 0.72x 13, or:
NetFullWidth = 9.35 kg
Scale the sample to a full hectare: Example:
93.5 = 9.35x 10, or:
NetPerHa = 93.5 kg/ha
Look up the number of meter shaft revolutions per ha:
CalCharRevs
for the current Drive Type, final sprocket and
transmission configuration. Example:
Drive Type 2, 20T and Standard is:
342 cup revolutions per ha.
CalChartRevs = 342
Detemine the cup rate for this seed mix: Example:
0.273 = 93.5 ÷ 342, or:
WeightPerRev = 0.273 kg
Determine the number of revolutions required for the
target field rate weight metered per shaft revolution: Example:
146 = 40
÷ 0.277, or:
TargetRevs = 146
Look up the Drive Type and final sprocket for
TargetRevs Example:
Drive Type: 1
Final Sprocket: 23 T
NetSample GrossWeight ContainerWeight – =
NetPerCup
NetSample
SampledRows
---------------------------------------
=
NetFullWidth NetPerCup 13 ×
=
NetPerHa NetFullWidth 10 × =
WeightPerRev
NetPerHa
CalChartRevs
--------------------------------------
=
T etRevs arg
T etRate arg
WeightPerRev
------------------------------------------
=