The paper deals with the description and analysis of the method of the additional earthing of the affected phase used for the elimination of the fault current during an earth fault in a compensated network. The efficiency of this method is strongly influenced by the fault location and resistance and, in some cases, its application can lead to deteriorating the situation at the point of the fault and thus to increasing the risk of dangerous touch voltage. The paper analyses the results of the simulations of selected fault cases where the negative influence of the additional earthing of the affected phase on the fault current magnitude (and therefore on the occurrence of the dangerous touch voltage at the point of the fault and in the neighboring LV network) can be expected. All the theoretical conclusions and assumptions were consequently verified by experiments in a real distribution network. Their results were then used in the final part as a basis for proposing the measures to apply the method in MV distribution networks.

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Rolling bearings are an important part of most machines with rotating parts. Therefore, their technical diagnostics is an essential condition for ensuring the safe operation of the machine. This article focuses on the assessment of the condition of bearings using one of the methods of technical diagnosticsvibration diagnostics. In our case it is determination of the value of diagnostic variables of rolling bearings with a subsequent prediction of their condition based on the evaluation of time series analysis. Theoretical knowledge and practices are verified based on measurement data obtained from single-row ball bearings of type 3208A in the manufacturer test room.