Dry fertilizer fan adjustment, A33 a14 – Great Plains 1625AHL Operator Manual User Manual
Page 59
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Great Plains Manufacturing, Inc.
Operating Instructions
55
2014-04-21
411-020M
Dry Fertilizer Fan Adjustment
Refer to Figure 43 through Figure 44
1625AHD models have a third Magnehelic
®
gauge
,
with a fan system decal (right wing, inboard of Air-Pro
®
gauge
). This gauge has a scale of 0-to-50 inches of
water pressure. Typical readings are in the 35-45 range.
This gauge reads pressure inside the fan manifold
The manifold supplies air to both the seed meters (meter
pressurization air) and to the dry fertilizer meter.
Approximately 10% of the air is tapped at the top end of
the manifold for meter pressurization air. The tap fraction
is controlled by a butterfly valve, which has an initial
factory setting of approximately 75
°.
Use the tractor remote lever to set fan speed. Use the
butterfly valve adjustment to adjust air fraction for seed
and fertilizer metering. The objective is to obtain
sufficient pressure to avoid dry fertilizer blockage, and
sufficient seed meter pressure to avoid seeding skips
during end-of-pass marker fold, lift and turn.
Adjustments may be required for different field speeds,
different fertilizer rates or fertilizer composition. For initial
static (parked, no material flow) setup:
1.
Look up the recommended meter pressurization for
the intended crop (see Seed Rate manual). Make a
note of the previous or factory settings of all butterfly
valves. Load seed in hoppers and meters. Meters
must be full to inlet shutters for valid readings.
2.
Close the manifold outlet butterfly valve
(set to 90
°). If the wing butterfly valves have been
previously adjusted for balance, leave them
undisturbed, otherwise set them full open (0
°).
3.
For setup, operate the tractor engine at typical field
rpms, and not at idle. Run the fan at maximum oil
flow without over-speeding.
4.
Adjust manifold outlet butterfly valve
to achieve
recommended pressure on the Air-Pro
®
gauges
5.
Re-check both pressures
in the field, with
material flowing at desired rates. Adjust fan speed to
stay within 35 to 45 inches. Adjust the manifold outlet
butterfly valve
to the suggested pressure for the
seed.
Check all pressure early in the first pass, with fertilizer
flowing and seed disk pockets full. Adjust fan speed as
necessary. Stop and adjust butterfly valves as needed to
keep gauges in the desired range.
When planting and applying, check the seed monitor for
skip/double and fertilizer blockage alarms. Check gauge
pressures with full meters and at field speed. Adjust the
fan rpm to compensate for average pressure shifts.
Re-adjust the manifold outlet butterfly valve
for
optimal meter pressurization.
Note: Fan speed and manifold pressures changes
between application and no-fertilizer-metering
states. Monitor fan rpm, meter pressurization,
fertilizer blockage detection and fan pressure
gauge during application and turns.
Note: Fan rpm is dependent on back-pressure due to
material flow. Fan speed increases when flowing
material, due to cavitation.
Figure 43
Fertilizer Manifold (Fan) Gauge
31187
858-193C
36134
A14
0
10
30
20
40
50
858-193C
A14
A15
Figure 44
Fertilizer Manifold Butterfly Valve
36134
858-208C
A16
A11
A15
A15
A14
A15
A15