Great Plains 3S-4000F Operator Manual - Manual (Page 58)

54 3S-4000 Table of Contents Index Great Plains Manufacturing, Inc.
195-394M Table of Contents Index 2014-06-10
Table at right shows the approximate force at openers for
a given pressure at the pressure control valve.
Note: To account for additional compaction from drill and
tractor tires, set pressure on center openers slightly
higher than wing openers.
Hydraulic Down Pressure All Openers
To run the drill with constant opener down pressure
requires an Active Hydraulic System. An Active Hydraulic
System requires a tractor with closed-center hydraulics
or pressure/flow compensated hydraulics powered by a
variable displacement hydraulic pump. (If you are not
familiar with your tractor’s hydraulics, consult your tractor
dealer.)
Tractors with load-sensing hydraulics must use the bypass
valve to operate the 3S-4000. Failure to use the bypass valve
can cause major tractor damage. Before adjusting opener
down pressure, set bypass valve as explained under “Setting
the Bypass Valve” on page 28.
Note: To run the drill on tractors with open-center
hydraulics or on tractors with fixed displacement
hydraulic pumps you must install a Great Plains kit,
part number 194-143A. Contact your Great Plains
dealer for ordering information. See “Non-Active
Hydraulic System” on page 32.
To set down pressure:
1. Lower openers to the ground. Lock hydraulic lever
forward for constant hydraulic flow.
You must lock hydraulic lever forward. See “Opener
Operation” on page 30, for instructions.
Refer to Figure 57
2.
Turn knob on pressure-control valve while watching
pressure gauge, turn knob until gauge shows
desired pressure. Turn clockwise to increase
pressure. Turn counterclockwise to decrease
pressure.
There is one pressure-control valve for openers on
the center section and one for openers on the wing
sections of the drill.
As a general starting point, set hydraulic down
pressure to 1000 psi. For most field conditions,
adjust down pressure between 200 and 1600 psi.
Hydraulic Down-Force
Gauge
Setting
Pounds of Force at Opener Disks
6 inch
rows
7 1/2 in
rows
10 inch
rows
200 PSI 83 86 92
300 PSI 90 95 102
400 PSI 97 103 113
500 PSI 103 111 124
600 PSI 110 119 135
700 PSI 117 128 146
800 PSI 123 136 157
900 PSI 130 144 167
1000 PSI 137 152 178
1100 PSI 143 161 189
1200 PSI 150 169 200
1300 PSI 157 177 211
1400 PSI 163 185 222
1500 PSI 170 194 233
1600 PSI 176 202 244
1700 PSI 183 210 254
1800 PSI 190 218 264
Figure 57
Pressure Control Valves
15557