Having introduced Australian broadacre growers to the benefits of low-weight aluminium booms and the country’s largest self-propelled sprayer – the 9,000 litre Rubicon – Hardi believes H-Select offers some unique advantages.

“H-Select uses four-head nozzle bodies arrayed in individual or selected boom sections,” a spokesperson said.

“An autonomous controller manages each section’s speed against the set spray rate, then switches the nozzle heads on and off rapidly and precisely in order to achieve consistent spray delivery across the turning boom.

“Unlike pressure adjusted turn compensation, which affects fluid velocity and therefore nozzle performance, switching between nozzle heads means the flow rate can be continually adjusted without ever compromising the size or speed of the droplets produced.

“Along with accurate rate delivery, that consistency is critical to effective crop penetration and drift control.

“The system also allows the operator to set and change the nozzle droplet size on the go, using H-Select’s in-cab run screen.

“It means a farmer can adjust their target droplet size to suit the day’s crop, coverage rate and spraying conditions.”

While similar switching technologies have appeared with two or three-nozzle heads, the four-nozzle solution is essential for covering the full range of delivery rates needed while turning wide booms around obstacles or in headland.

“If you’re making a 50 metre radius turn at 20km/h, the inner end of a 48.5 metre boom will slow down to just 10.3 km/h while the outer tip will accelerate to 29.7 km/h.” Hardi product manager for self-propelled sprayers Steven Lancaster said.

“In other words, the tip-to-tip speed range of 19.4 km/h is almost equal to the forward speed of the sprayer, and the flow rate will need to double across the boom.”

H-Select technology integrates with existing systems on its largest Rubicon sprayers as the controller operates on the same electronics platform.