Accuracy and testing

15 May 2019

How accurate is the SAM spread pattern?

Very accurate. Representative machines have been regularly tested using the nationally recognised Spreadmark test for accuracy. This involves collecting data from catch trays and graphing the results. Spread patterns are rated using Coefficient of Variation (CV), a measure of the percentage of fertiliser outside a perfect spread being 0% making the perfect spread pattern.

New Zealand standards recognise a CV under 15% as acceptable for nitrogenous fertilisers (DAP, Urea, Nitroposka Blue etc.) SAM Spreaders tested achieve a 7.1% CV of Urea and 8.1% CV for Superphosphate. This is a very accurate spread and well within industry standards.


Is there an optimal spreading centre distance?

We recommend spreading at 15m centres for granulated fertiliser products and 10 metre centres for powdered or fine granulated products such as lime. This will give you a nice even spread pattern. You can spread wider (up to 20m) but accuracy may be affected slightly the wider you go.