Acquisition of diagnostic information from the indicator diagrams of marine engines using the electronic indicators

The paper analyzes the factors influencing the quantity and quality of diagnostic information obtained by engine indication with electronic indicators and pressures analyzers. Amount of information obtained virtually unchanged since the advent of the first construction pressure analyzers produced by Autronica and ABB Company. In many cases, the value of the maximum combustion and compression pressures, can be measured using these devices with sufficient accuracy and reliability, is if ignition occurs after piston TDC. Determination of the mean indicated pressure, compression ratio and heat release characteristics required to develop a method of TDC determination on the indicator diagrams, generate reliable angular axes in real time and pressure sensors of sufficient accuracy. It should be noted that in the latest solution of ABB system, a correction of thermodynamic loss angle and combustion pressure sensors of high accuracy were introduced. For marine diesel engines diagnosis, the pressure sensor measuring sustainability is important because of the ability to create trends of specific diagnostic parameters, which may constitute an additional, important source of diagnostic information. The paper presents an overview of currently available pressure sensors that can be used during marine engines indication. Most important issues related to the pressure measurement on indicator valves were characterized. An assessment of the gas channels and the quality of the angular axis impact for the parameters of indicator graphs was done.