47HARDI® N-SERIES 3-PT SPRAYER DIAPHRAGM OPERATOR'S MANUAL5.5 Calibration (Pasture sprayer model only)WARNING: ALWAYS CALIBRATE YOUR SPRAYER WITH CLEANWATER ONLY! IN ADDITION, WEAR PROTECTIVECLOTHING WHEN CALIBRATING YOUR SPRAYER!Why must you calibrate a sprayer?A nozzle selection chart will tell you what application rate you shouldexpect. Variations due to nozzle wear, errors in pressure adjustment,and tractor speedometer can result in a possible error in applicationrate.How do you calibrate a sprayer?Calibration kits are available from HARDI® , #818493 for US gallons 󇴼 for metric calibration.Following are some tips to remember when using the calibration kitmethod:• When determining the length of time required to drive the recom-mended distance, drive in actual field conditions with a half-full tank.• Repeat the test several times, each time avoiding the tracks from theprevious test. Take the average of the times recorded.• Calibration of the sprayer should be completed at the beginning ofthe season and repeated after every 2 to 3 full days of spraying, andevery time you change volume rate or use new nozzles.• Before you calibrate, check the flow of each nozzle. If it puts out morethan 10% of its original volume, replace it.
