Great Plains 1625AHL Material Rate - Manual (Page 85)

Great Plains Manufacturing, Inc. Table of Contents Dry Fertilizer Rates 81
2014-03-17 Table of Contents 411-020B
14. Determine a ratio to use for a new setting.
Note: The effect of the gearbox adjuster is nearly linear in
the 30 to 70 range of the scale.
15. Subtract the calibrated rate per hectare (or acre)
from the target rate to determine a correction
difference.
16. Adjust the control arm by the number of degrees
needed to adjust for the calibration difference.
17. Run the calibration again, starting at step 9, using
the new Variable Rate Gearbox scale setting. This
validates the gearbox adjustment.
18. Remove and store the calibration crank. Wipe down
the calibration door, seal and lower face of meter.
Close the calibration door. Empty the bag into the
hopper.
This completes fertilizer rate calibration.
Metric Example:
FieldRate :
104
CorrectionFactor =
104
÷ 96.7,
which is:
1.08 (108%)
USc Example:
FieldRate :
93
CorrectionFactor =
93
÷ 86,
which is:
1.08 (108%)
The calibration run metered too little.
You must raise the gearbox setting to compensate.
CorrectionFactor
FieldRate
CalibratedRate
----------------------------------- =
Note: The rate of the arm adjusting crank is more than
one scale degree per turn, and the crank can only
be pinned at quarter turns. Pin it when the indicator
is closest to the new setting.
Metric Example:
PriorGearboxSetting :
28
NextGearboxSetting =
28 × 1.08
which is:
30
USc Example:
PriorGearboxSetting :
29
NextGearboxSetting =
29 × 1.08
which is:
31
NextGearboxSetting PriorGearboxSetting CorrectionFactor Ч =