Great Plains 1625AHL Operator Manual - Manual (Page 58)

54 1625AH Table of Contents Index Great Plains Manufacturing, Inc.
411-020M Table of Contents Index 2014-04-21
Balancing Wing Pressures
Refer to Figure 42
For any model planter, the in-frame manifold inlet
on
each wing has a butterfly valve . These valves are
normally set to full open (0 °).
It is unlikely, but possible that a pressure imbalance
could occur in the field. This might appear as skips or
low rates from the rows on one side. If this happens:
1. Raise the fan rpm (any planter) or (dry fertilizer
models only) open the fan butterfly valve (page 55)
until the low side is seeding normally.
2. Adjust the butterfly valve on the other (higher rate)
wing to match readings on both meter pressurization
Magnehelic
®
gauges.
For a liquid fertilizer planter, continue at “Liquid
Fertilizer Planter Fan Adjustment” on page 54.
For a dry fertilizer planter, continue at “Dry Fertilizer
Fan Adjustment” on page 55.
Liquid Fertilizer Planter Fan Adjustment
Use the tractor remote lever to set fan speed.
As necessary use butterfly valves adjustment to make
fine adjustments to meter pressurization. Precise
technique depends on tractor capabilities:
• The objective is to obtain recommended meter
pressurization, and maintain it during end-of-pass
marker fold, lift and turn.
• For any setup adjustment, operate the tractor engine
at typical field rpms, and not at idle.
• Preset butterfly valves. Use any settings previously
developed for the crop/disk/range. On a new planter,
start with both wing butterfly valves fully open.
If the tractor has fine control of remote flow rates, and
consistent flow at varying tractor engine rpm, initially
set the butterfly valves 0
°, or in any case to 30° or less.
If the tractor has only coarse control of flow, initially set
the wing butterfly valves to 45
°.
• Set the fan circuit flow to bring the gauge reading to
near the recommended value.
• Fine tune the meter pressurization with the wing
butterfly valves.
• If the tractor has marginal flow available, or the lift
circuit has priority, you may need to experiment with
combinations of fan flow and butterfly valve settings.
Adjust the fan to provide the meter pressurization
recommended for the seed disk, seed, and seed density.
See the tables and charts for recommended values in
the Seed Rate Manual.
Figure 42
Wing Inlet Butterfly Valve
36134
A19
A18
A18
A19