Patent ID: 6911830
Filing Date: 2005-06-28
Classification: G01N

Abstract:
1. A method for determining engine lubricating oil condition of a Diesel engine, comprising the steps of: measuring a selected one of conductivity and conductance of lubricating oil of a Diesel engine at a frequency above of about 2 MHz to thereby provide a first measured value; measuring the selected one of conductivity and conductance of the oil at a frequency below about 1 KHz to thereby provide a second measured value; measuring a temperature of the oil taken substantially contemporaneously with said second step of measuring; determining a first oil condition constant, m; determining a second oil condition constant, b; wherein m and b are determined based upon a predetermined relationship with respect to the measured temperature; calculating a ratio, Y, of the first measured value with respect to the second measured value; calculating a contaminant concentration, X, based upon a relation: determining whether X has reached a predetermined threshold; wherein if X is below the threshold, then the engine oil condition has a first condition; and if X is at least one of at the threshold or above the threshold, then the engine oil condition has a second condition.