Placement Machine Assessment
Calibrating a placement machine flows a parallel process to broadcast equipment. However, because the fertiliser is discharged directly to the ground, it can be measured directly at the outlets. Because all the fertiliser can be caught, the application rate calculations will be accurate. The uniformity still compares how evenly the fertiliser is distributed among the outlets.
Enter Vehicle Details
In FertSpread, the placement machine option is selected in the Vehicle Details Screen.
Enter the vehicle details so you can compare tests later. The travel speed is required – if you enter the travel Distance and Travel Time it will calculate the speed. Or you can enter the speed directly if you know it accurately. GPS speeds can be accurate, but speedometer readings are often incorrect, and a field check of time to cover distance is valuable.
Complete the Placement PTO Details.
Grey boxes are good information for future reference. The yellow boxes are required – fill in the Bout Width and Number of Outlets boxes, and the Outlet Width will be auto-filled.
Fertiliser Details
In the Fertiliser Details screen, enter the fertiliser being used. This is imprtant as different products will perform deifferently in a machine.
The Nitrogen Based Y/N box and the Target Application Rate box must be completed.
The remaining fertiliser information is good information to include as the quality also affects the discharge rate, and hence the Application Rate.
Catch Details
Enter the fertiliser weights you measured from each outlet. An example of collecting and weighing the fertiliser from each outlet is shown in the video below.
Once this is done, click continue and the calculations will be completed. You can view the report and check the performance is as you expect. If you see some outlets applying different amounts, check the machine for blockages, leaks or poorly adjusted splitters.
View Report
In the example report, we see that all the outlets are applying fertiliser within the accepted band for nitrogen fertilisers (the Blue and Red lines on the graph).
The Measured Rate (Brown line) is close to the Target Rate (Green line). We might change the speed slightly or make a discharge door adjustment to get closer.
The CV of 5% is a very even distribution, which we should expect from a placement machine. Overall, we would say this is a good result.