This thesis provides a detailed steps for the configuration of the protection settings, using the DIGSI 4 software package by Siemens, for the numerical relay protection of autotransformer (with a stabilization tertiary winding). The relay type 7UT6x is employed for that purpose. Following protection functions of the said relay have been employed for the autotransformer protection: differential protection, REF protection, overcurrent protection, thermal protection and overexcitation protection. Parameters of the current and voltage transducers for the concrete application were selected as well. All necessary parameters of the protected object, current and voltage transducers, as well as protection function settings, were configured on the relay, in the offline mode, using the DIGSI 4 software package by Siemens.