Great Plains YP825A Operator Manual - Manual (Page 56)

52 YP425A, YP625A and YP825A Table of Contents Index Great Plains Manufacturing, Inc.
401-651M Table of Contents Index 2014-08-15
5. Rate: Seed Inlet Shutter
A consistent seed results from having a consistent
number of seeds (usually one) in each pocket of the
seed disk, avoiding “skips” (fewer seeds per pocket) and
“doubles” (excess seed per pocket).
Refer to Figure 46
One of the factors that affects seed pickup at the disk is
having an optimal seed pool (page 75). The depth of the
seed pool is controlled by the seed inlet shutter
.
Each Seed Rate chart specifies a suggested initial
shutter setting. See “Seed Inlet Shutter Adjustment” on
page 74 for setting details, and further adjustment.
At unused rows, set the shutter to zero/closed to prevent
loss of meter pressurization air. Install a blank disk. See
“Row Unit Shut-Off” on page 77.
6. Rate: Meter Pressurization
Refer to Figure 47
(which depicts a typical reading for some densities of corn)
A major factor that affects seed pickup at the disk is
optimal meter pressurization. Fan air holds the seed in
the disk pockets until they pass the drop brush
(page 42).
The Seed and Fertilizer Rate manual has a section with
suggested initial manifold pressures, which may be a
single value, or a graph based on seed density.
Manifold pressure is set by a combination of tractor
circuit lever and fan butterfly valve (page 41). See “Air
System Operation” on page 37.
7. Rate: Checking
Although the seed monitor reports a computed
population based on seeds sensed, only an actual furrow
check provides certainty about the actual seeding rate.
See the Seed and Fertilizer Rate manual.
Figure 46
Seed Inlet Shutter: Setting III
29607
5
5
Figure 47
Manifold Pressure Gauge
29842