FIELD: technological processes; data processing.SUBSTANCE: measurement system for use in analysing operation of process equipment within a process comprises a plurality of sensors including at least one non-intrusive sensor arranged within the process. Each of the plurality of sensors measures a different physical process phenomenon within the process. Non-intrusive sensor measures the corresponding physical process phenomenon without contact with the process. Logic module is communicatively coupled to each of the plurality of sensors to receive the sensor measurements, and comprises a logic means and a model that relates measurements of the values of each of the different physical process phenomenon to a further physical process phenomenon. Logic module operates on a computer processor device to determine a value of the further physical process phenomenon using the model and the sensor measurements.EFFECT: system is configured to measure or determine process phenomena, direct measurement of which is impossib
