Great Plains NTA2007HD Operator Manual User Manual
Page 81
Great Plains Manufacturing, Inc.
Adjustments
77
04/04/2011
166-283M
Null4:
28. Determine the amount of rate change for each
degree of control arm rotation from the target setting.
If the calibrated rate was
higher than target (as in our example),
examine lower gearbox setting values.
If the calibrated rate was
lower than target,
examine higher gearbox setting values.
29. Adjust the control arm by the number of degrees
needed to adjust for the calibration difference.
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 corrected setting.
30. To validate the adjustment, run the calibration again,
starting at step 14 on page 75, using the new Vari-
able Rate Gearbox scale setting.
This validates the gearbox adjustment, and will gen-
erate a new, more precise Calibration Constant.
31. With the present meter satisfactorily calibrated, re-
mount the final drive gear removed (if any) from the
meter on the other hopper.
32. Repeat the calibration procedure for the other hop-
per, starting at step 1 on page 73.
33. Continue at “Calibration Closeout” on page 79.
TargetRate
Null4:
Metric Example:
Initial Variable
Rate Gearbox
Setting: 62
163.7
183.5
59
78794
169.0
189.4
60
78916
174.3
195.4
61
79050
179.6
201.3
62
79197
185.0
207.4
63
79357
31374
Null4:
USc Example:
Metric Example:
1 degree lower reduces rate by
67.6-63.9, or 3.7 lbs
201.3 - 195.4, or 5.9 kg
2 degrees lower reduces by
67.6-60.4, or 7.2 lbs
201.3 - 189.4, or 11.9 kg
3 degrees lower reduces by
67.6-56.9, or 10.7 lbs
201.3 - 183.5, or 17.8 kg
USc Example:
Metric Example:
The calibration difference was:
8 pounds.
17 kg
Adjusting down 2 degrees
would correct by 7.2
pounds, but adjusting by 3
would over-correct to 10.7
lbs.
Adjusting down 3 degrees
would slightly over-correct,
at a difference of 17.8 kg
So adjust the gearbox
setting to just over 2
degrees lower, to a final
scale setting:
So adjust the gearbox set-
ting to just under 3 degrees
lower, to a final scale set-
ting of:
slightly below 36
slightly above 59