Algorithms and Models for Evaluation of Technical Characteristics of Low-voltage Electrical Apparata

The paper reflects the problem of evaluating the efficiency of low-voltage switching devices, which are used in the systems of in-plant power supply. The technical condition of circuit breakers and contactors of different manufacturing plants has been investigated, models for determining the technical characteristics of switching devices have been developed. The dependences of active power losses in the investigated devices on the current flowing through them have been established. The result of research is approximating functions of the value of active power losses and contact resistances from the main parameters of switching devices. Developed algorithm and models for assessing the efficiency of operation of devices, which allow to specify the value of active power losses and electricity in low-voltage electrical networks.