Great Plains 3P600 Material Rate - Manual (Page 7)

Great Plains Manufacturing, Inc. Table of Contents Main Box Rates Main Box Seed Rate 5
2011-10-21 Table of Contents Main Box Rates 118-794B
Main Box Seed Rate Calibration
Differences will exist between the tested seed and field
conditions used to generate the Seed Rate Charts, and
your seed and conditions. To accurately achieve your
target population, Great Plains recommends calibrating.
Due to the large number of crank revolutions per acre
(786 or 982) and per hectare (1942 or 2427), a practical
calibration is a simulation of
1 ⁄
10
th
acre or
1 ⁄
10
th
hectare.
1. Estimate the sample sizes.
2. To perform this calibration, you need a scale that is
accurate at the aggregate sample size, and three (3)
light containers, each capable of holding the
expected SamplePerRow. Record the empty
container weights.
3. Raise the drill so the gauge wheel is just out of
ground contact.
4. Remove the calibration crank from its storage stob.
Store the retaining pin on the stob.
Note: On older drills lacking a calibration crank, you can
crank the gearbox input jackshaft, by means of a
wrench or socket, for the same number of rotations
as shown for “Crank” in the table. You can
alternatively rotate the gauge wheel tire. A
calibration crank upgrade kit is available (see
Operator manual 118-794M).
Refer to Figure 7
5.
Place the hex socket of the crank on the left end of
the main jackshaft.
6. Pull the seed hoses off the top of three opener seed
tubes, at the top of the openers. Place the hoses into
each sample container.
Calibration Revolutions
Figure 7
Calibration Crank
32793
Drill Model Rotations Per ...
3P500 Acre Hectare
Crank 982 98.2 2427 243
Tire 1752 175 4329 433
Drill Model Rotations Per ...
3P500V Acre Hectare
Crank 982 98.2 2427 243
Tire 1752 175 4329 433
Drill Model Rotations Per ...
3P600 Acre Hectare
Crank 786 78.6 1942 194
Tire 1402 140 3464 346
32366
1 / 10
th ac. 1 / 10
th ha
1 / 10
th ac. 1 / 10
th ha
1 /
10
th ac. 1 /
10
th ha
Example: You want to apply barley at 60 pounds per
acre with a 3P600 7.5 inch drill. RateSample is:
Example: the drill has 9 rows. SamplePerRow is:
Example: 3 rows are to be used in the sampling.
ExpectedSample is:
The expected sample weight is 2.0 lb.
Example: 3 containers, each weighing 0.5lb:
ContainerWeight = 1.5 lb
6.0
60
10
------
=
0.67
6.0
9
--------
=
2.0 0.67 3 × =
RateSample
FieldRate
10
---------------------------- =
SamplePerRow
RateSample
RowCount
------------------------------------ =
ExpectedSample SamplePerRow SampledRows Ч
=