Great Plains 2020P Operator Manual - Manual (Page 39)

4/23/2010 118-740M
37 Adjustments
Equations for calibrating volumetric seeding rate:
measured seed empty container –
3 (number of meters measured)
----------------------------------------------------------------------------------------- pounds per meter =
Checking Volumetric Seeding Rate
The seed charts are based on cleaned seed and
11L x 15, rib implement tires. Factors including for-
eign material, seed treatment, seed size, seed
weight, field conditions and tire pressure will affect
seeding rate. Set and check the seeding rate, then
readjust the rate as necessary.
1. Record the weight of an empty container large
enough to hold seed metered from three meters
for one acre.
2. Place several pounds of seed over three seed
meters on an outside end of the drill box.
NOTE: If drill box is full, shut off sliding seed
tubes to all but three meters on an outside end.
3. Raise drill off ground.
4. Turn gauge wheel a few turns to fill meters with
seed and until seed drops to ground from all
three openers.
5. Place a container under the three openers to
gather seed as it is metered.
6. Using the chart on the next page, select your
row spacing and determine the correct number
of revolutions per acre. Turn drive gauge wheel
the selected revolutions for your row spacing.
Check in box to make sure seed tubes have
plenty of seed covering them.
7. Weigh measured seed. Subtract initial weight of
empty container. Divide by three for the amount
metered by each meter, then multiply by the
number of drill openers for the pounds-per-acre
seeding rate.
8. If seeding rate is different than desired:
• Double check transmission sprocket and
drive range sprocket combinations.
• Check for meter malfunction.
• Check for correct seed meter wheel.
• Check that all three rows are getting seed.
• Refer to Troubleshooting on page 47.
9. Readjust transmission and/or range sprockets
and repeat test.
pounds per meter number of openers
×
pounds per acre =