Great Plains 1625AHL Material Rate - Manual (Page 81)

Great Plains Manufacturing, Inc. Table of Contents Dry Fertilizer Rates 77
2014-03-17 Table of Contents 411-020B
Dry Fertilizer Range Gears
Refer to Figure 18
The meter flute shaft
is driven by the agitator shaft
through a pair of interchangeable gears , . The
positioning of these gears creates two final drive ranges.
Each rate chart is based on a specific Final Drive Range.
The Ranges are:
• “High” range, which is used for higher fertilizer rates
• “Low” range, which is used for lower fertilizer rates
The two seed meter shafts are labelled “DRIVING” and
“DRIVEN”.
The “DRIVING” shaft is the upper/forward shaft.
The “DRIVEN” shaft is the lower/rear shaft.
Refer to the Seed Rate Chart (or Fertilizer Rate Chart),
the table below, and Figure 18 for setting the seed meter
final drive range.
1. Remove the lynch pins from the gear ends of both
shafts.
2. Remove and position the gears as shown in the table
above.
3. Secure with lynch pins.
Setting Variable Rate Gearbox
The variable rate gearbox allows an arbitrarily variable
meter drive speed to attain a wide range of metering
rates. The ratio of gearbox input speed to output speed is
controlled by the position of a gearbox control arm. The
control arm has an indicator that points to a scale
marked in degrees. The Fertilizer Rate Charts show the
rate for each degree setting.
Refer to the rate charts and set the variable rate gearbox
control arm to its scale setting for the target rate.
To adjust the Variable Rate Gearbox:
Refer to Figure 19
1.
Remove the hairpin cotter securing the gearbox
adjustment crank .
2. Rotate crank until the control arm indicator points
to the scale setting that matches the rate from the
chart, or as determined by calibration.
3. Re-insert the hairpin cotter.
Note: The variable rate gearbox operates optimally
between 30 and 70. If your rate is listed on both the
Low Range and High Range charts, select the
chart where your rate results in a gearbox control
arm setting between 30 and 70. Settings below 20
degrees are not recommended. When the control
arm is set above 70 degrees, large movements of
the arm result in small changes in rate.
Figure 18
HIGH Final Drive Range
34500
FINAL DRIVE
RANGE
DRIVING DRIVEN
LOW RANGE 17 Tooth Small 54 Tooth Large
HIGH RANGE 54 Tooth Large 17 Tooth Small
2
1
3
4
DRIVING
DRIVEN
1 2
3 4
Figure 19
Variable Rate Gearbox at 0
34501
5
6
7
5
6
7