Great Plains 800 Material Rate - Manual (Page 30)

175-057B Table of Contents Main Box Rates 2011-10-25
28 800 Table of Contents Main Box Rates Great Plains Manufacturing, Inc.
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 fertilizer.
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 beginning on
page 31.
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.
Perform the calibration with opener frames lowered
(if the openers are raised, the clutch disengages).
Leave the tractor hitched for movement control.
Due to the large number of crank revolutions per acre
(728) and per hectare (1799), a practical calibration
would be 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.
Figure 8
Small Seeds Rate Handle
32634
1
2 1
2
Figure 9
Calibration Crank Stored
28067
Example: You want to apply alfalfa at 12 pounds per
acre with your 12-row 7
1 ⁄
2
inch drill.
Example: the drill has 12 rows:
Example: 3 rows are to be used in the sampling:
The ExpectedSample weight is 0.3 lb.
Example: 3 containers each weighing 0.23 lb or:
0.69 lb total
1.2
12
10
------ =
0.10
1.2
12
--------
=
0.30 0.10 3 × =
RateSample
FieldRate
10
----------------------------
=
SamplePerRow
RateSample
RowCount
------------------------------------ =
ExpectedSample SamplePerRow SampledRows
Ч
=