flow rate chosen for the equipment. 7. Follow nozzle manufacturer's recom- mendation for proper nozzle height.
BOOM SPRAYER CALIBRATION: KNOWN AREA METHOD (FIGURE 3)
1. Measure a level test course at least 100 feet long on a turf area (not a parking lot or cart path). The width of this test course will be the spacing between each nozzle in feet. Nozzle Spacing in Inches divided by 12
= Test Course Width in Feet. Total square feet of the area is Length X Width. 2. Fill machine 1/2 full of water to sim-
ulate average load and record the exact number of seconds to travel the entire test course at normal operating speed. Use a calibration jar to collect the flow from each nozzle for the same amount of time it took to cover the test course. Calculate the aver- age nozzle output and replace or clean any nozzle with a flow rate not within 5% of the average. Average Nozzle Flow in Ounces divided by 128 oz. per gallon = Av- erage Gallons Applied 3. Record all data for future use. Calcu-
late your + or - 5% acceptable error range (Target Area vs. Sprayed Area). Each time you use your sprayer, the calibration rate must fall within these values. Either repair or replace components causing calibration rate inaccuracy.
TIPS: Check for wear more frequently when spraying wettable powders. Verify the accuracy of your measuring devices.
EASY METHOD SPRAYER CALI- BRATION (128TH ACRE TEST)
equal (record in inches). 3. Perform nozzle uniformity test. 4. Measure test course. (Use chart
1. Fill spray tank with clean water. 2. Verify that spacing between nozzles is
below or formula to determine course length.) (Formula: 4080 / Nozzle Spacing in Inches = Test Course in Feet.) 5. Drive the test course at your normal spraying speed and record travel time in seconds. 6. Park sprayer while maintaining the same engine RPM used to drive the test course.
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FIGURE 3
FIGURE 2
