Great Plains YP4425A Operator Manual User Manual
Page 91
Great Plains Manufacturing, Inc.
Troubleshooting
87
2012-02-23
401-805M
Overall High
Population,
cont.
Speed sensor angle.
With planter lowered, check radar speed sensor angle per
DICKEY-john
®
recommendations.
Incorrect speed sensor constant
Perform speed calibration per DICKEY-john
®
monitor
manual.
Overlapping passes
Check marker extension (page 150).
For GPS, check planter size programmed.
Actual field size is different
Population may be correct, and calculations are not.
High
Population,
Single Row
Excess meter pressurization causing
doubles
Check shutter.
Worn seed-drop brush and/or strip
brushes allowing excess seed to
pass
Replace worn brushes.
Incorrect seed disc with higher cell
count.
Install correct disc.
Population Too High
Problem
Cause
Solution
Population Related
Problem
Cause
Solution
Overall
Population
Alarms
False alarms or actual rate errors
due to monitor setup with
incorrect [active] row count or
spacing
When troubleshooting population issues, always first rule out
seed monitor setup. Review planter configuration and monitor
setup.
Incorrect cell count
Replace seed discs with correct discs, or reset rate for current
discs (if within range).
Improper gap on speed sensor.
Check speed sensor on planter for
1
⁄
16
in to
1
⁄
8
in (1.6-3.2mm)
gap from wheel. Improper gap can cause erratic speed signal
causing monitor to falsely report improper planting rate.
Incorrect speed sensor constant
Perform speed calibration per DICKEY-john
®
monitor
manual.
Mismatch
Between
Reported and
Furrow
Population
Small seeds (example milo) are
not reliably sensed in the seed
tube
Run with rain covers in place to minimize ambient light
intrusion. Use the population adjustment factor in the
DICKEY-john
®
monitor system to compensate for missed
seeds. For example, change the DICKEY-john
®
Population
Adjustment values from 100% to 130% or 140% as needed.
Remember to set this back to 100% for large seeds.
Seed tube sensor is not counting
all seeds
Clean the seed tube of graphite and dust buildup with long
narrow seed tube brush. Replace sensors that malfunction.
Seeds / revolution value in the
DICKEY-john
®
setup does not
match the disc cell count.
Correct the value in a setup screen or install the correct cell
count disc.
Excessive
Seed
Cracking
Incorrect seed pocket size
Use correct disc for seed.
Damaged, old or dried-out seed
Use new seed.
Unclean seed
Use clean seed.