Method for monitoring of a wind power plant operated in variable operating states. Start sensor data is obtained in at least one basic operating state of the machine; based on the start sensor data, a starting model with a rule set for conducting the monitoring is set up, the rule set determining which parameters are to be monitored, in which manner and with which weighting and which sensor data are to be obtained and used for this purpose; a reference SOM is prepared using the rule set with sensor data selected using the rule set and obtained in a reference operating phase of the machine; during a monitoring operating phase, time characteristics of a quantization error of the sensor data selected using the rule set being tracked with respect to the reference SOM, troubleshooting being started if the quantization error meets a criterion which is dictated by the rule set.