Great Plains NP30A 30-foot Operator Manual - Manual (Page 92)

88 NP30A or NP40A Table of Contents Index Great Plains Manufacturing, Inc.
407-502M Table of Contents Index 2014-05-20
3-Section and 2012- Weight Transfer
For 2013+ 5-Section weight transfer, see page 90.
See important safety information on page 87.
Refer to Figure 68 and Figure 69 (depicting NP3000)
Wing fold cylinders can extend, during field operation,
to push the wings down using mainframe/center weight.
Weight transfer is enabled by opening the weight-transfer
shut-off valve
, and controlled by two adjustment
valves ( and ). See circuit diagrams on page 150 or
page 151. The fold circuit is set to continuous flow (in
unfold mode) to maintain the active weight transfer.
The weight-transfer shut-off valve must be open for
weight transfer. When closed, it bypasses the reducing
valve for faster fold cylinder operation (and faster 2-point
lift-assist).
The pressure reducing valve controls the flow to the
cylinders.
The bypass valve returns excess oil to the tractor.
Adjust the weight transfer to achieve consistent coulter
depth, while keeping the wings level with the center
section. If insufficient weight is transferred, outside
(wing) coulters may run higher than center section. If too
much weight is transferred, center section may run high.
If adjusted when the tractor is cold, re-adjustment may
be required when the oil warms. Monitor the pressure
gauge during early field operations.
Refer to Figure 68 on page 88 and Figure 70
1.
In field conditions, unfold (page 58), lower applicator
(page 48), and set or check application depth
(page 91).
2. Pull forward to put coulters in ground.
3. Put tractor in Park and set parking brake.
4. Open weight-transfer shut-off valve .
5. Release the bypass valve lock disc . Turn the
bypass valve knob fully clockwise to shut-off all
bypass oil flow. Tighten lock disc.
6. Set tractor to half throttle. Adjust tractor flow control
valve so that wings fold/unfold at a reasonable
speed. Keep tractor running for step 7 through
step 10.
Note: On 2-point applicators, fold and unfold are followed
by lift and lower operations.
Figure 68
3P Weight Transfer
31581
2
3
1
1
2 3
1
2
3
Figure 69
Weight Transfer Valves
32041
2 3
1
1
4
5