Great Plains NP4000 40-foot Operator Manual - Manual (Page 68)

407-776M Table of Contents Index 2012-03-28
64 NP4000 Table of Contents Index Great Plains Manufacturing, Inc.
Fertilizer Rate
Rate setting is materially different for each pump type:
• Ground Drive: rate is positively set by the drive system
and piston pump dial.
• Hydraulic Drive: rate is set on the console.
The console operates a flow control valve. The valve
adjusts the rate up to the peak value available at the
current setting for hydraulic pump rpm.
Adjustments to orifice plates must also be made to
provide back-pressure, keeping the boom within a
specific safe pressure range that assures consistent
delivery.
Rate Setting Steps:
1. Determine the rate (below).
2. Install suitable orifice plates (page 69).
3. Check strainer screen size (page 71).
4. Ground Drive: Set the ground drive Range
(page 72), and ground drive dial (page 72).
Hydraulic Drive: Set the pump pressure (page 73);
set the desired rate on the console (see
016-0159-831 Raven SCS-450 Installation,
Operation and Service manual).
5. Check the manifold pressure and relief valve during
operation (page 71).
Determining Application Rate
Great Plains recommends checking with your local
agronomist as soil conditions vary. Soil conditions in your
area may need less or more fertilizer than represented in
the chart.
If your target rate is weight per area, you need to know
the material density to convert it to liquid volume
measure:
If you want to use the slide chart, and have only a metric
rate value, convert it to U.S.customary units:
Ground Drive:
The tables, and web calculator provided expect rates to
be expressed as
[U.S.customary] gallons per [U.S.Survey] acre or
liters per hectare.
The slide chart provided is gal/ac only.
Volume_per_Area Weight_per_Area Density ÷
=
Gallons_per_Acre 0.107 Liters_per_Hectare Ч
=