The mathematical model of load, used in the monitoring of electrical network operational dynamics, is suitable to describe different types of loads. The structure of the mathematical model is the same for all loads. In order to use the load model to describe specific loads, the model parameters must be estimated. If the existing data is not sufficient to evaluate all parameters of the model, type-models – a typical sets of model parameters – may be used. Irrespective of initial information, the result is always a complete model that describes all necessary details of the load. However, the accuracy of the model and its applications are dependent on availability of initial data and on the quality of type models.