Great Plains NTA3007HD Operator Manual - Manual (Page 82)

78 NTA907HD or NTA3007HD
166-207M 04/04/2011
Meter Calibration
Push and then and then to
get to meter calibration.
The Seed Rate charts are based on cleaned untreated
seed of average size and test weight. Many factors affect
meter rates including foreign material, seed treatment,
seed size, field conditions, and test weight. The Fertilizer
Rate chart is based on a representative granular fertil-
izer.
Great Plains recommends calibrating for the exact mate-
rials you intend to apply. Calibration determines two very
important settings for achieving accurate rates:
• The kilograms per hectare (or pounds per acre) of the
meter at the current variable rate gearbox setting for
your particular seed or fertilizer.
• The Calibration Constant for the monitor to accurately
report the planting rate of your particular seed or fertil-
izer.
Calibration Procedure
The seed monitor must be correctly set up for both the air
drill and the material(s), or the calibration will not result in
useful monitor displays. The right column contains an
example for the following steps.
1. Set the Final Drive Range gears and Variable Rate
Gearbox setting to the values suggested in the Seed
Rate Chart (or Fertilizer Rate Chart).
2. Make sure there is enough material in the hopper(s)
for at least
1 ⁄
10
hectare (or
1 ⁄
10
acre) plus an extra
35 to 45 kg (75 to 100 lbs.).
Refer to Figure 83
3.
Since only one calibration bag is provided, remove
one of the final range gears
from the meter that is
NOT being tested, to disable it.
4. Open the calibration door of the meter being cali-
brated. The calibration door is the rear of the two
bottom doors.
Do not open the door under the upper DRIVING gear. This is
the clean-out door. Opening this door will drain the hopper.
Once this door is open it is difficult to stop seed flow until the
hopper is empty.
Null4:
See the Seed Rate manual for an example in U.S. cus-
tomary units.
Example: Wheat, High Rate, 2 Stars
Target Seed Rate: 200 kg/ha
Initial Variable Rate Gearbox setting: 62
Null4:
Figure 83
Calibration Door Open
26339
F
R
1
2
1
2