BOOMSPRAYER consultant Bill Campbell likes to keep it simple.
Which was a relief for more than 20 John Deere self-propelled boomsprayer owners, who were in Esperance recently, attending AFGRI Equipment’s Owners’ Spray Day.
The focus was on John Deere’s new 4060 self-propelled boomsprayer, equipped with Deere’s new ExactApply intelligent nozzle control system.
Most owners had a rudimentary understanding of the ExactApply as a Pulse Width Modulation (PWM) system – spraying at a constant set pressure and droplet size, regardless of the sprayer speed and application flow rate.
The operator has the ability to automatically vary the rate across the entire boom, ensuring the uniform application of chemical, even while turning.
The system also reduces the number of nozzles needed because of the increased range on each nozzle and as added bonus, LED lighting on each individual nozzle improves visibility of the spray pattern in low-light conditions.
But like all computerised systems, it’s the degree of how much information is accurate that determines the efficiency and ‘knowledge’ of a computer – the old garbage in, garbage out principle.
So the news from Mr Campbell at the start of the day immediately allayed fears of old timers.
“The basic principles of spraying technology haven’t changed,” Mr Campbell said.
“Smaller droplets never make it, bigger droplets give poorer coverage.
“So you should always be aiming for sweet spots.”
While lauding the ExactApply system as “very clever” providing the ability to “mix and match” (spray nozzles with pressure, water volumes and speed), Mr Campbell was insistent that attention to set-up was vital to produce a desired result.
“Be careful reading claims about nozzles,” he said.
“Some manufacturers use different standards depending in what country the nozzles are made and some can be a degree finer than what is required for Australian conditions.
“You can have the best system in the world but if the spray is leaving the boom, it’s being wasted.”
It was important to understand droplet size and the relationship to the nozzle size and water rate.
“Test the nozzles you buy with water-sensitive paper and remember that efficacy is measurable with things like the SnapCard app or portable scanning systems,” Mr Campbell said.
“By checking, you can pick up things like a nozzle operating better at say 5.2 Bar than 3.3 Bar.
“And check the calibration of nozzle flow rate in terms of litres a minute.
“Play around with your nozzles at set-up and know what they are doing, not just on the horizontal but also on the vertical.
“Look at the (spray) plume out the back of the boom.
“It needs to be falling not leaving the boom.”
According to Deere, ExactApply provides sprayer operators with “a comprehensive solution that maintains consistent droplet size and pattern through a wide range of speeds, while reducing the potential for overlaps, skips and drift.”
The company said its PWM system offered three times the pulsing frequency of traditional PWM systems on a wide variety of nozzles.
There’s also the ability to switch spraying between two pre-selected nozzles with the push of a button to increase the range of application to achieve consistent droplet size.
ExactApply is fully integrated with the GreenStar 2630 Display and SprayStar, making it compatible with the entire suite of John Deere precision and data management products.
Because of the electronics associated with each ExactApply nozzle body, Mr Campbell said it was easy to envisage in the future, such systems could be fitted with cameras for spot-spraying.