Fan general operating information – Great Plains 3PYPA Operator Manual User Manual
Page 49
Great Plains Manufacturing, Inc.
Operating Instructions
45
03/20/2012
401-647M
Fan General Operating Information
Use tractor remote hydraulic valve flow control to set fan
speed. Always start the fan with a low flow setting.
Monitor fan rpm with the seed monitor.
Gradually bring fan up to the recommended initial rpm.
The split-air servo vane engages only above 50 rpm.
Do not run the fan over 3900 rpm or at speeds under
2000 rpm.
At excessive rpm, too much air flow can cause:
• seed to plug the air box
• seed suspension in a bulk seed box
• oil heating
• slow lift times
If the rpm is too low, the split-air system may divert
nearly all the air to meter pressurization, leaving none for
seed transport (or just enough to plug low spots in seed
hoses).
The monitor console can report meter pressurization.
There is also a Magnehelic® air pressure gauge. These
two readings should not disagree by more than a few
tenths of an inch.
If at suggested fan rpm, desired pressure cannot be
reached, chances are the fan is running backwards. If
the rpm and meter pressurization readings are correct,
but the meters are starved of seed, the fan may be run-
ning backwards and the meter pressurization system is
taking all the air, leaving little or none for seed delivery.
Reverse the inlet/return lines at the hitch.
If air system does not operate suitably with fan speeds
between 2000 and 3900 rpm, see “Seed Delivery Trou-
bleshooting” on page 93.
When starting empty you must blow seed out to the
meters for two to four minutes to fill meters.
The monitor has a level sensor below the hopper or seed
box to warn when seed box is empty. There are three to
four acres of seed in the system when the sensor first
indicates box empty, depending on seeding rate.
Steps for setting and adjusting the air system are found
at “Fan and Adjustment” on page 62.
Recommended Fan Speeds
3PYPA
Seed Hopper*
Bulk Box
Initial Fan Speed
2900 rpm
2500 rpm
Fan Speed Range 2000 - 3900 rpm 2000 - 3300 rpm
Oil Consumption
Ground Drive
16 - 24 gpm
16 - 22 gpm
No Markers
61 - 92 lpm
61 - 82 lpm
Ground Drive
23 - 31 gpm
23 - 28 gpm
With Markers
85 - 116 lpm
85 - 106 lpm
Hydraulic Drive
21 - 29 gpm
21 - 26 gpm
No Markers
78 - 109 lpm
78 - 99 lpm
Hydraulic Drive
28 - 36 gpm
28 - 34 gpm
With Markers
106 - 137 lpm
106 - 127 lpm
34 - 42 gpm
34 - 40 gpm
Maximum Turns
129 - 160 lpm
129 - 150 lpm
Maximum Config.
* This assumes a 2007+ Great Plains hopper, or older hopper
with the vent line update. For an older unvented hopper, use
the rpms recommended for Bulk Box.
Metadata: Recommended Initial Fan Speeds
Low Population Risk at Turns:
The figures assume a 6 second lift and 15 second marker fold,
and do not include oil consumed by the tractor itself. Aggres-
sive lift/lower operations, and simultaneous lift/marker opera-
tions, can reduce fan rpm below that needed to pressurize
meter disks. If seeds fall out of pockets, low population bands
will occur after turns.
Unless the tractor has generous oil flow capacity, raise/fold
markers before lift, and lift slowly. Watch manifold pressure
and tune operations to keep it at planting levels in turns.
The Seed Rate manual provides initial values for meter
pressurization. Normal readings are in the 0.8in to 4.0in
water range, and vary considerably with crop.
During “FILL METER”, all air is routed to the air box,
and none to the meter pressurization system.
Recommended Fan Speeds