1. A method for the early notification of an abnormal event detection (AED) of equipment groups of a polymers process unit comprising: (a) comparing online measurements from an array of sensors for the process units to a model in a set of models including principal component analysis models for normal operation of the corresponding process units, wherein said polymers process unit has been divided into at least two equipment groups and process operating modes wherein there is minimal interaction between said equipment groups and one of said principal component analysis models corresponds to equipment groups and process operating modes, wherein the inputs to the principal component analysis models include measurements from said array of sensors, (b) determining if the current operation differs from expected normal operations from the cumulative measurements of said sensors that are inputs to said model so as to indicate the presence of an abnormal condition in an equipment group which has developed on a timescale of minutes to hours, and (c) determining the underlying cause of an abnormal condition in the polymers process unit.