Great Plains YP825A Operator Manual - Manual (Page 62)

58 YP425A, YP625A and YP825A Table of Contents Index Great Plains Manufacturing, Inc.
401-651M Table of Contents Index 2014-08-15
Refer to Figure 55
2.
Row orifice setup:
Orifice plate sizes are chosen to assure
consistent pressure at all nozzles, with the 15-40 psi
range. See the Seed and Fertilizer Rate manual for
sizing and installation.
Unused rows may be shut off by exchanging the
nozzle for a cap
. Plates at the active line usually
need to be changed at shut-off or turn-on. See the
Seed and Fertilizer Rate manual for details.
Material Loss or Misapplication Risks:
Orifice size must be appropriate for rate selected. Drop line
orifice plates do not affect rate. If orifice size is too small,
over-pressure in system may result in material loss at relief
valve. An orifice size too large may result in uneven
application across all rows.
When shutting off rows, review orifice sizing.
Refer to Figure 56
3.
Relief valve setting:
See the Seed and Fertilizer Rate manual for details
on setting this valve.
Once set for a given fertilizer density, the valve only
requires seasonal review.
During operations, monitor the gauge and the dump
line . Watch for the following conditions:
• A reading below 15 psi usually indicates a need for a
smaller orifice size.
• A reading in the ideal 15-40 psi range, but with
material appearing at the dump line , indicates a
need to increase the operating pressure of the
valve
.
• A reading at or near 65 psi, with material appearing at
the dump line , usually indicates a need to increase
orifice size (or plugged orifices).
• A reading above 65 psi indicates a need to reduce the
operating pressure of the valve .
Figure 55
Fertilizer Drop Line Nozzle
29984
1
2
Agricultural Chemical Hazard:
Wear protective gloves when exchanging orifice plates. 1
2
Figure 56
Fertilizer Relief Valve
31017
3
4
5
3
4
5
5
3
5
3