Great Plains YP1625 Operator Manual - Manual (Page 51)

Great Plains Manufacturing, Inc. Adjustments 47
03/12/2012 401-226M-A
Checking Planting Rate
Cautious practice includes checking seed delivery rate
prior to planting.
Although the seed monitor can reliably count singulated
seeds, it does not count individual volumetric seeds, and
several factors can cause even singulated reports to be
inaccurate (such as incorrect speed calibration, Sensor
Constant or Gear Ratio setup).
Methods of rate checking are described in detail in the
Seed Rate Manual. The information on this page is an
overview of the general process, which varies with the
seed type and the planter meter drive type.
Before checking rate, make sure that the seed monitor is
configured with an accurate Ground Speed Constant. As
delivered, the monitor may have an inappropriate value
pre-loaded.
The DICKEY-john Quick Start Guide for your planter
includes an initial value for this constant, but this value
may not be optimal for your planter, and does not include
any adjustment for tire wear over time.
For reliable monitor reports, at the start of each season,
perform a “GROUND SPEED CALIBRATION” over a
400ft/100m course, as described in the DICKEY-john
Intelli-ag Planter/Drill Control Operator’s Manual. When
completed and entered in the monitor, cross-check the
reported implement speed against the tractor speedome-
ter or other reference.
Checking Singulated Rate
A furrow check is the most accurate way to verify that
you are seeding at your desired population value. This is
done by planting for a short distance with one or two
rows set to shallow depth and with press wheels tied up
for no furrow closure. Seeds are counted in the furrow
over a specific distance and the area rate is computed.
Refer to the Seed Rate Manual for details.
The seed monitor will also be counting during the test,
and comparing results provides confidence in the seed
monitor display.
Note: If the checked rate varies materially from the chart
rate, or for hydraulic drive, from the programmed
rate, it is likely that there is a planter malfunction
(such as contact drive tire slippage) or a configura-
tion error that requires correction. Do not “calibrate”
to correct unexpected variations in singulated
rates.