Great Plains TA520S Operator Manual - Manual (Page 54)

1993-1995 Tandem Axle Sprayer
500-061M 3/18/2005
52
3. Turn the left boom section switch off and keep the
center and right section switches on. Unscrew the
throttling valve for the left boom section until the
pressure on the boom pressure gauge reaches the
calibration pressure. Flip the left boom section
switch a few times and adjust the throttling valve so
that the pressure remains at the selected calibration
pressure.
4. Turn the left boom section switch on. With the left
and right boom sections on, turn the center boom
section off and adjust the throttling valve as de-
scribed in step 3.
5. Adjust the throttling valve for the right boom section
with the left and center boom sections on as de-
scribed in step 3.
6. With all throttling valves adjusted, it should be pos-
sible to flip any combination of boom section switch-
es with the pressure remaining constant.
Pressure Adjustments {Manual Con-
trol System Only}
One of the most important areas of controlling the spray-
er accuracy is to have the proper pressure when
spraying. The pressure is determined when the sprayer
is calibrated. Refer to "Calibration Procedures", start-
ing on page 28.
The electric ball valve is used to adjust the pressure to
the booms. It is controlled with the pressure adjust
switch on the control box. The boom pressure is dis-
played by the boom pressure gauge.
To adjust the pressure, hold the pressure adjust toggle
switch up for more pressure, down for less pressure. If
holding the switch up decreases pressure, reverse wires
at the ball valve. Refer to Figure 10 on page 19 (8).
As the tank level decreases, the boom pressure may
change. Check your boom pressure gauge frequently
and make sure that the pressure doesn’t change. Gen-
erally, the boom pressure will need to be adjusted up
slightly when the tank level decreases.
When the manual pressure adjustment valve {refer to
"Plumbing Diagrams" beginning on page 22} is wide
open, the pressure adjust switch is very sensitive. To de-
crease the sensitivity of the pressure adjust, set the
manual pressure adjustment valve.
To set the manual pressure adjustment valve, open the
electric ball valve wide open with the pressure adjust-
ment switch. Shut the manual pressure adjustment valve
down so the pressure is about 20 psi greater than the
pressure you will spray at {the pressure the spray will be
applied at is determined when you calibrate your spray-
er. Refer to "Calibration Procedures" on page 28}.
With this valve set, it will decrease the flow through the
electric ball valve and reduce the sensitivity of the pres-
sure adjustment switch.
Elevator Slide Adjustment
Refer to Figure 19
The elevator slide is initially adjusted at the factory so
that the slide blocks have the correct tolerances be-
tween the blocks and the vertical elevator tuber. Over
time the blocks will wear and may need to be adjusted.
To adjust the slide blocks, adjust the slide block clear-
ance bolts (1) so that the slide frame is centered and
parallel with the elevator frame. Make sure all blocks
have 1/32 of an inch clearance between the block and
the vertical tube when finished.
Note: With the boom mounted, there will be 1/16 of an
inch clearance on the top rear and lower front blocks.
The other blocks will be touching the tube due to the
weight of the boom.
Figure 19
Elevator Slide Adjustment
11952