Lift system, comprising: a central control unit for generating control signals and/or for processing sensor signals and for controlling functions of the lift system; a plurality of field devices (17a, 17b, 17c, 17d) which are arranged in a distributed manner inside a structure which accommodates the lift system, in particular preferably along a lift shaft, wherein each field device (17a, 17b, 17c, 17d) is set up to output sensor signals generated by a sensor and/or to receive control signals to be implemented by an actuator; a field bus system having a topology of electrical lines for interchanging sensor signals and/or control signals between the central control unit and the field devices (17a, 17b, 17c, 17d); wherein the field devices (17a, 17b, 17c, 17d), the central control unit, and the field bus system are designed to interchange a data packet comprising the sensor signals and/or control signals in a serial manner between the central control unit and all field devices (17a, 17b, 17c, 17d) in a summation frame method using a closed ring topology; wherein each of the field devices (17a, 17b, 17c, 17d) has a driver (33, 33') in order to insert the sensor signals into the data packet or to remove the control signals from the data packet, wherein the field devices (17a, 17b, 17c, 17d) are arranged one behind the other in a sequence, wherein the plurality of field devices (17a, 17b, 17c, 17d) is divided into a first group (17a, 17c) comprising at least one field device, and a second group (17b, 17d) comprising at least one field device, wherein, on an outbound path of the ring topology from the control unit as far as a field device (17c; 17d) that is arranged furthest from the control unit, only the field devices (17a, 17c) of the first group are incorporated into the ring topology such that the data packet is supplied to the drivers thereof, whereas the field devices (17b, 17d) of the second group are incorporated into the ring topology on a return path of the ring topology from the control unit as far as a field device (17c; 17d) that is arranged furthest from the control unit, such that the data packet is supplied to the drivers thereof, wherein the first group of field devices comprises just every second field device (17a, 17c) on the path of the ring topology from the control unit to the field device (17c, 17d) arranged furthest from the control unit. a central control unit for generating control signals and/or for processing sensor signals and for controlling functions of the lift system; a plurality of field devices (17a, 17b, 17c, 17d) which are arranged in a distributed manner inside a structure which accommodates the lift system, in particular preferably along a lift shaft, wherein each field device (17a, 17b, 17c, 17d) is set up to output sensor signals generated by a sensor and/or to receive control signals to be implemented by an actuator; a field bus system having a topology of electrical lines for interchanging sensor signals and/or control signals between the central control unit and the field devices (17a, 17b, 17c, 17d); wherein the field devices (17a, 17b, 17c, 17d), the central control unit, and the field bus system are designed to interchange a data packet comprising the sensor signals and/or control signals in a serial manner between the central control unit and all field devices (17a, 17b, 17c, 17d) in a summation frame method using a closed ring topology; wherein each of the field devices (17a, 17b, 17c, 17d) has a driver (33, 33') in order to insert the sensor signals into the data packet or to remove the control signals from the data packet, wherein the field devices (17a, 17b, 17c, 17d) are arranged one behind the other in a sequence, wherein the plurality of field devices (17a, 17b, 17c, 17d) is divided into a first group (17a, 17c) comprising at least one field device, and a second group (17b, 17d) comprising at least one field device, wherein, on an outbound path of the ring topology from the control unit as far as a field device (17c; 17d) that is arranged furthest from the control unit, only the field devices (17a, 17c) of the first group are incorporated into the ring topology such that the data packet is supplied to the drivers thereof, whereas the field devices (17b, 17d) of the second group are incorporated into the ring topology on a return path of the ring topology from the control unit as far as a field device (17c; 17d) that is arranged furthest from the control unit, such that the data packet is supplied to the drivers thereof, wherein the first group of field devices comprises just every second field device (17a, 17c) on the path of the ring topology from the control unit to the field device (17c, 17d) arranged furthest from the control unit.