Great Plains 2510HDP Material Rate - Manual (Page 39)

Great Plains Manufacturing, Inc. Main Seed Box Planting 37
12/01/2009 118-245B
Calibrating Volumetric Seed Rate
This procedure is for ground drive. If you have hydraulic
drive, see Hydraulic Drive section of Operator Manual.
The seed charts are based on 11Lx15 rib implement
tires inflated to factory specifications, operating at chart
speed, and a single variety of clean seed.
Factors including seed size/weight, seed treatments,
field conditions and foreign matter in the seed, cause
variations from chart rates. Check the rate. Some adjust-
ment may be needed.
1. Record the total empty weight of one or more con-
tainers just large enough to hold the seed from three
row units and one acre (or hectare).
2. Pick which rows to test on the drill. Outside rows are
the easiest to work around.
If the seed box is empty, and you have seed corks
available, block adjacent rows. Otherwise, shut off
those rows at their sliding seed tube caps.
3. Prepare an amount of seed for 3 rows and one acre
(or hectare), plus 10 pounds (or 5 kg). Load it over
the openers to be tested.
If seed is already loaded across all rows, shut off the
rows not tested at their sliding seed tube caps, and
disengage those meters at the drive couplers. Shut-
off is necessary only for the box being tested, the
drive for the other box is not operating during the
test.
4. Consult the Seed Rate charts, and configure the
Range and Transmission sprockets for your seed,
meter wheel and desired population.
5. Raise the drill. Place the sample containers under
the seed tubes of the rows under test.
6. For the tested drill section, rotate the ground drive
gauge wheel a few turns until meters are filled with
seed and seed is metering consistently from the
seed tubes. Stop, and return the seed to the seed
box. Return empty containers to test rows.
7. Note the number of tire rotations per acre, from “Tire
Rotations” on page 54.
8. In the table at right, note the wheel rpm for the rec-
ommended ground speed from the Seed Rate chart.
Use this rpm for testing. Turning too slowly or too
rapidly has unreliable results compared to actual
planting.
Example:
2510HDP-2910 drill, in standard 10in row spacing
Seed: barley
Wheel 403-085D Wheat Wide
Population desired: 108 lbs/ac
(note: nearest chart rate is 106.9)
TotalPopulation = 108
Example (step 1):
Three containers weighing 7 oz. empty
21 = 3 x 7
ContainerWeight = 1.31 lbs total empty weight
Example (step 2):
2510HDP-2910 has 29 rows, 3 used in test
PopulationFraction = RowsToTest / RowsToPlant
0.1034 = 3 / 29
Example (step 3):
Expected population for 3 rows and one acre:
SamplePopulation = TotalPopulation x PopulationFraction
11.2 lbs = 108 x 0.1034
Load about 21 pounds for testing
Example (step 7):
TireRotations = 221/acre; 546/hectare
Example (step 7):
TireRotations = 221/acre; 546/hectare
Example (step 8):
Recommended Planting Speed (
mph )
for barley at 108 lbs/ac and 10in row spacing is:
8 mph
Ground Speed - Gauge Wheel rpm
Speed 4 5 6 7 8
kph 6.4 8.0 9.7 11.3 12.9
rpm 44 55 66 77 88