System (Sys) for fail-safe supplying of an electrical consumer (E) with a redundantly designed energy bus (EB), via which decentralised functional units (E, S, W, Bue, AC), which are arranged in a rail safety installation and can be characterised as electrical consumers, are supplied with electrical energy, wherein: a) a higher-level controller system (STW) is provided, which exchanges information with the decentralised functional units (E) by means of data telegrams via a data bus (CB), b) network node units (SND) are arranged sequentially between two feed points (PS1, PS2) of an energy bus (EB) with an annular construction, which provide the decentralised functional units (E) with access to the energy bus and optionally also to the data bus (CB), c) the network node units (SND) possess a switch module (S) which can be controlled by a control unit (CPU), which comprises a first switch (S1) and a second switch (S2), wherein access to the two feed points (PS1, PS2) can be switched by the two switches (S1, S2), d) there is provision on each side of the decentralised functional unit (E) for a resistor subassembly (RG1, RG2) arranged between the positive conductor (Bus+) and the negative conductor (Bus-) of the energy bus (EB) in each case, the output of which (A1, A2) is connected to an input of a switch group (S3, S4) in each case, which connects one of the two conductors (Bus+, Bus-) of the energy bus (EB) to the decentralised functional unit (E), wherein the resistor subassembly (RG1, RG2) is configured such that the switch group (S3, S4) connects through in the presence of the bus voltage; and e) a control output (ST1, ST2) connected to the output of the resistor subassembly (RG1, RG2) in each case, with which the output voltage provided by the resistor subassembly (RG1, RG2) can be manipulated. a) a higher-level controller system (STW) is provided, which exchanges information with the decentralised functional units (E) by means of data telegrams via a data bus (CB), b) network node units (SND) are arranged sequentially between two feed points (PS1, PS2) of an energy bus (EB) with an annular construction, which provide the decentralised functional units (E) with access to the energy bus and optionally also to the data bus (CB), c) the network node units (SND) possess a switch module (S) which can be controlled by a control unit (CPU), which comprises a first switch (S1) and a second switch (S2), wherein access to the two feed points (PS1, PS2) can be switched by the two switches (S1, S2), d) there is provision on each side of the decentralised functional unit (E) for a resistor subassembly (RG1, RG2) arranged between the positive conductor (Bus+) and the negative conductor (Bus-) of the energy bus (EB) in each case, the output of which (A1, A2) is connected to an input of a switch group (S3, S4) in each case, which connects one of the two conductors (Bus+, Bus-) of the energy bus (EB) to the decentralised functional unit (E), wherein the resistor subassembly (RG1, RG2) is configured such that the switch group (S3, S4) connects through in the presence of the bus voltage; and e) a control output (ST1, ST2) connected to the output of the resistor subassembly (RG1, RG2) in each case, with which the output voltage provided by the resistor subassembly (RG1, RG2) can be manipulated. <EOS>