The paper presents a computational verification of the sensitivity of the 95% earth fault protection of the motor-generator stator in RHE Velebit. The occurrence of a single-pole short circuit in the 400 kV incident network is considered, as well as the transfer of the corresponding zero voltage via the capacitive path via the associated block transformer to the voltage level of the mentioned motor-generator. The values of the measured capacities of the relevant block transformer are used.