Great Plains 3P600 Material Rate - Manual (Page 35)

2011-10-21 Table of Contents Main Box Rates 118-794B
Great Plains Manufacturing, Inc. Table of Contents Main Box Rates 33
Small Seeds Rate
Seeding rate from the optional Small Seeds Attachment
is controlled entirely by the seed rate handle on the small
seeds box. No sprocket changes are required, and small
seeds rate is unaffected by settings for main seed box
and optional Native Grass.
Refer to Figure 8
To set Small Seeds rate, loosen the wing nut
at the
handle. Move the lever until the indicator is about 10
higher than the intended setting, then return it to that
setting. Tighten nut.
Set the initial rate based on the charts starting on
page 36.
Small Seeds Rate Calibration
Differences will exist between the tested seed and field
conditions used to generate the Small Seeds 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 near the aggregate sample size, and
three (3) light weight containers, each capable of
holding a row’s sample.
3. Raise the drill so the gauge wheel is 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).
Figure 8
Small Seeds Rate Handle
32634
1
2
1
2
Example: You want to apply alfalfa at 12 pounds per
acre with a 3P600 7.5 in. 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 0.4 lb.
Example: 3 containers each weighing 0.23 lb or:
0.70 lb total
1.2
12
10
------ =
0.133
1.2
9
-------- =
0.40 0.133 3 ×
=
RateSample
FieldRate
10
---------------------------- =
SamplePerRow
RateSample
RowCount
------------------------------------
=
ExpectedSample SamplePerRow SampledRows
Ч
=