Great Plains YP825AR Operator Manual - Manual (Page 61)

Great Plains Manufacturing, Inc. Table of Contents Index Adjustments 57
2014-06-17 Table of Contents Index 401-923M
14. Skips:
If all else is correct, and the overall average
population is running low (or there are gaps upon
furrow check), the cause may be seeds falling out of
disk pockets before delivery to the seed tube.
Increase meter pressurization to correct this.
Note: Insufficient meter pressurization, or unusually
rough fields, can increase the incidence of empty
pockets. Be sure to rule out other causes (such as
skipping chains, meter starvation, incorrect meter
disks) before adjusting meter pressurization to
reduce apparent skips.
15. Doubles:
If all else is correct, and the overall average
population is running high (or there are double seeds
upon furrow check), the cause may be two seeds in
some disk pockets at delivery to the seed tube.
Decrease meter pressurization to correct this.
Note: Excess meter pressurization can increase the
incidence of doubles. Be sure to rule out other
causes (such as incorrect meter disks) before
adjusting meter pressurization to reduce doubles.
Fine-Tuning Meter Pressurization
After several passes, and you are comfortable with the
planter’s operation, you can optimize meter
pressurization. Use this method during longer passes, so
there are fewer distractions (and see sidebar regarding
Milo).
16. Observe the current overall average population
reported by the monitor.
17. Adjust the fan speed down, in small steps, waiting
5-10 seconds between adjustments, until skips occur
(actual population begins falling below target). Note
the pressure at which skips begin.
18. Restore pressure to the initial value at step 16.
19. Adjust the fan speed up, by periodic small
increments, until doubles occur (actual population
begins rising above target). Note the pressure at
which doubles begin.
20. Adjust meter pressurization to a value halfway
between the limits established at step 17 and
step 19. This is the ideal value for your crop, disk and
population, providing equal margin against skips and
doubles. Record this value for future use.
Alternate Skip/Double Check
Small seeds, particularly Milo, are less reliably sensed as
skips or doubles by the seed tube sensors, and watching
monitor population is unlikely to locate the pressure
limits. This test can also be quicker for all seeds.
A. After planting a few passes with initial settings,
remove the rain covers from several rows (use rows
with a variety of seed hose lengths and routes).
B. Make a meter pressurization adjustment. Resume
planting for a pass or less.
C. Stop planter motion but leave engine at field rpm and
fan running.
D. Inspect the seed disks closely. Look for empty seed
cells (skips) and cells with multiple seeds (doubles).
E. Repeat step B-to-step D until limits are established.
Record limits. Re-install rain covers. Plant with
median settings.