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HARDI
MEGA 230 / 350 CENTRIFUGAL OPERATORS MANUAL
Formula:
distance (ft.) x 0.68
seconds
= MPH
6.15 Calibration (cont'd)
Formula Method
1. Check your spraying speed.
Measure a test strip of at least 200 feet (300 feet is ideal). Travel the
distance at the speed you plan on spraying and record the time it takes
to travel the distance. Read from the chart or use the formula to find
your exact travel speed.
Travel Time (in seconds)
Speed in MPH
200 ft.
300 ft.
3.0
45
68
3.5
39
58
4.0
34
51
4.5
30
45
5.0
27
41
6.0
23
34
7.0
19
29
7.5
18
27
8.0
17
26
9.0
15
23
Note:
W= • Nozzle spacing (in inches) for broadcast
application.
• Row spacing (in inches) divided by number of
nozzles per row for drop nozzle application.
• Sprayed band width or swath width (in inches)
for band application divided by number of nozzles
per band.
• Note that on the nozzle wheel, W = 20 inches.
3. Set correct pressure.
Read the required pressure from the nozzle table in the nozzle
catalogue or nozzle wheel. With clean water in the tank and line, turn
on the sprayer and set the target pressure. Collect the spray from one
nozzle for one minute in a container. Adjust pressure until you collect
the precise GPM called for.
Formula:
GPA x MPH x W (in.)
5940
GPM =
Formula:
10 x 7 x 20
5940
GPM =
= .24 GPM
2. Calculate the required nozzle output. Use either the nozzle wheel (if
nozzle spacing is 20 inches), or this formula:
