DGI-1570 (Dekati® Gravimetric Impactor) is a cascade impactor designed for measuring particle size distribution from engine exhaust. It is a gravimetric impactor which can replace a standard filter holder and is therefore easy to add to existing emission measurement systems.
In DGI the size classified particles are collected on Ø47 mm substrates and analysed gravimetrically or chemically after the measurement. The nominal sample flow rate is 70 lpm which enables high sample yield even during short measurement periods.
In standard setup the DGI size classifies particles into 5 size fractions with stage cutpoints of 2.5, 1.0, 0.5 and 0.2 µm. In modified setup two lowest stages are removed and the backup filter collects particles smaller than 1 µm. The backup filter size is 70 mm in diameter.