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SECTION 7
SPRAYING INFORMATION
STEP 7 - FIT & TEST SELECTED NOZZLES
The most important calibration is to test for the actual
litres per hectare achieved through your sprayer.
• Use the following method to fit and test the
selected nozzles:
• Fit selected nozzles to the sprayer.
• Fill your spray tank to maximum capacity & set the
specified pump pressure and operate the sprayer for a
short period to make sure all lines are full and nozzles
are working properly (no blockages, leaks etc).
• Stop the sprayer and top up the tank with water to
maximum capacity again.
• Operate the sprayer in the stationary position at the
required pressure for not less than one minute.
• Measure how much water is required to refill the tank
to the brim.
• Now, divide the volume measured by the time taken
(minutes). The longer the test time the more accurate
the figure.
The calculation formulation is;
Output (L/min) =
Output (litres)
Time (minutes)
Example 1, testing Tier 1 of our examples above.
28.5 litres
1.25 minutes (75 seconds)
= 22.8 litres/min.
Which is slightly more than the target of 22.4L/min
(0.56 L/min per nozzle x 40 nozzles for 1.0 min)
Example 2, testing Tier 2 of our examples above.
42.1 litres
1.25 minutes (75 seconds)
= 33.7 litres/min.
(note 0.86 L/min per nozzle x 40 nozzles for
1.0 min = 34.4 L/min)
• Excessive output is a sign of worn nozzles.
Refer to steps 8 & 9.
• Insufficient output is a sign of blockages.
Refer to steps 8 & 9.
STEP 8 - CALCULATE THE ACTUAL
APPLICATION RATE
Actual application rate is the objective of setting up and
calibrating your sprayer.
To calculate actual application rate (litres per hectare), use
the following formula:
Application Rate (L/ha) =
Total sprayer output (L/min)
x 600 ÷ speed (Km/hr) ÷ row spacing (m)
÷ number rows in one pass
Example 1
(as per Tier 1 example)
22.8 (L/min) x 600
÷ 7.5km/hr ÷ 3m (row spacing)
÷ 2 (rows/pass)
= 304 litres/ha
Example 2
(as per Tier 2 example)
33.7 (L/min) x 600
÷ 7.5 km/hr ÷ 3m (row spacing)
÷ 2 (rows/pass)
= 449 litres/ha
Summary of Contents for CROPAIR 300
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