Korrelationskoefficienten r for den lineære regression mellem GSE og GEXHW skal være mindst 0,95. Middelafvigelsen på estimatet af GSE mod GEXHWEXHW må ikke være over 5 % af GSE maks. GSE, regressionslinjens skæring, må ikke være over ± 2 % of GSE maks.
Such a procedure is required if the transformation time of the particulate system, t50,P or/and the transformation time of the exhaust mass flow signal, t50,F are > 0,3 s. Acorrect control of the partial dilution system is obtained, if the time trace of GEXHW,pre of the pre-test, which controls GSE, is shifted by a “look-ahead” time of t50,P + t50,F .