Great Plains 3N-3020 Material Rate - Manual (Page 26)

196-366B 4/28/2004
Great Plains Mfg., Inc.
26
Checking Volumetric Seeding
Rate
The seed charts are based on cleaned seed and
11L x 15 rib implement tires and 13 x 5.00-6 con-
tact drive wheel tires. Factors including foreign
material, seed treatment, seed size, seed weight,
field conditions and tire pressure will affect seed-
ing 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 measured from
three cups for one acre.
2. Place several pounds of seed over three seed
cups on an outside end of the small seeds
box. Raise drill off the ground.
3. Remove hose ends from the openers of the
three seed cups being measured.
Refer to Figure 35
4. Turn contact wheel clockwise a few turns to fill
cups with seed and until seed drops to ground
from all three hoses.
5. Place a container under the three hoses to
gather seed as it is measured.
6. Turn contact wheel clockwise 420 revolutions.
Check in box to make sure seed cups have
plenty of seed covering them.
7. Weigh measured seed. Subtract initial weight
of empty container. Divide by three for the
amount measured by each cup, 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 drive range sprocket combina-
tions.
• Check to be sure all three seed cups are cov-
ered with seed.
• Adjust seed-rate handle accordingly.
9. When finished reconnect seed hoses to op-
ners.
Equations for calibrating volumetric
measured seed empty container –
3 (number of cups measured)
------------------------------------------------------------------------------------------ pounds per cup =
pounds per cup number of openers × pounds per acre =
19114
Figure 35
Contact Drive Wheel