A method for monitoring a nuclear plant includes, for each steam generator from among a plurality of steam generators and for at least one of the parameters of a set of parameters representative of operating of the steam generator, determining a deviation between a measured value of the parameter for this steam generator and the average value of this parameter for all the steam generators to detect an imbalance of this parameter on the steam generator; and characterizing the imbalance as a function of one or more other parameters in the set of representative parameters, so as to generate a physical problem signal or a measurement drift signal.