Air and seeding system overview – Great Plains YP825AR Operator Manual User Manual
Page 50

46
YP825AR
Great Plains Manufacturing, Inc.
401-923M
2014-06-17
Air and Seeding System Overview
Refer to Figure 47, on page 45, and Figure 48.
The hydraulic fan
supplies air exclusively for meter
operation. Fan rpm is operator-adjusted (page 48),
normally via the tractor circuit’s hydraulic flow control.
A manually-adjusted butterfly valve
is provided at the
fan outlet. See page 48 for valve adjustment.
The manifold system
delivers fan air across the
planter. It includes passive internal design features to
balance pressure across the planter.
Separate pressurization tubes
route manifold air to
each row unit.
Seed is delivered from the seed box
by gravity to the
inlet of the Air-Pro
®
seed meter
.
A manually adjusted inlet shutter
controls the size of
the seed pool
at the base of the meter. The shutter
also minimizes air loss back up the seed inlet tube, and
is also used during row shut off. See page 74 for shutter
adjustments.
At the meter, pressurization air exits the meter through
the seed pockets
of the disk, and holds seed in the
pockets until released above the seed tube
.
In the seed tube, the seed sensor
detects passage of
seeds. Medium size and large seeds are counted
individually. With smaller seeds, most are detected,
allowing the monitor to detect stoppages.
Several rows have a pressure sensor port
for the
meter pressurization system. A line
from each of
these rows is connected to a chamber
to average the
pressures.
The averaged pressure is reported by a Magnehelic
®
gauge
visible to the tractor operator. See page 56 for
use of the gauge in making fan adjustments.
A sensor
in each seed tube reports seed passage to
the seed monitor. Larger seeds are counted individually.
For smaller seeds, the system acts as a blockage
monitor.
Note: Use of the special blank disk (page 78), and closing
the seed inlet shutter (page 74), are particularly
important when a sensor row is shut off.
Note: On any row, running a normal disk with no seed, or
with an open empty inlet, unbalances the air
system. Doing either at a sensor row causes the
gauge to mis-report as well.
Note: Do not operate in the ground with the fan shut off, or
with insufficient manifold pressure. The meters will
completely fill with seed. Meter clean-out may be
required to resume normal operation.
Figure 48
Air-Pro
®
Meter, Disk Side
31040
12
10
8
4
7
6
9
11
1
2
3
4
5
6
7
8
9
10
12
13
14
15