Separator having a frame and a separator insert exchangeably arranged on the frame, a) wherein the separator insert is designed to separate a flowable suspension into at least two flowable phases (LP, HP) of different density in a centrifugal field and forms a pre-assembled, exchangeable unit for insertion into stator units on the frame of the separator and comprises at least the following: i. a housing which is stationary in operation and is designed in the manner of a container which is closed except for one or more openings, ii. a rotor arranged inside the housing and rotatable about an axis of rotation, having a drum which has one or more openings, iii. preferably a separating means arranged in the drum, iv. at least two rotor units (4b, 5b) for magnetic bearing devices (4, 5) at two axially spaced locations of the rotor with the drum, by means of which the rotor with the drum can be held in suspension, is rotatably supportable and can be made to rotate within the housing in operation, b) wherein furthermore mutually spaced holders (I-4, I-5) having stator units (4a, 5a) of the bearing devices (4, 5) are formed on the frame, between which holders the housing of the separator insert is non-rotatably retained such that the rotor remains rotatable with the drum, c) wherein the relative position of the holders (I-4 and I-5) having the stator units (4a, 5a) of the bearing devices (4, 5) can be changed such that the separator insert can be exchanged, d) wherein the housing and at least one of the holders (I-4 and I-5) have corresponding interlocking elements in order to non-rotatably retain the housing on the holder. a) wherein the separator insert is designed to separate a flowable suspension into at least two flowable phases (LP, HP) of different density in a centrifugal field and forms a pre-assembled, exchangeable unit for insertion into stator units on the frame of the separator and comprises at least the following: i. a housing which is stationary in operation and is designed in the manner of a container which is closed except for one or more openings, ii. a rotor arranged inside the housing and rotatable about an axis of rotation, having a drum which has one or more openings, iii. preferably a separating means arranged in the drum, iv. at least two rotor units (4b, 5b) for magnetic bearing devices (4, 5) at two axially spaced locations of the rotor with the drum, by means of which the rotor with the drum can be held in suspension, is rotatably supportable and can be made to rotate within the housing in operation, i. a housing which is stationary in operation and is designed in the manner of a container which is closed except for one or more openings, ii. a rotor arranged inside the housing and rotatable about an axis of rotation, having a drum which has one or more openings, iii. preferably a separating means arranged in the drum, iv. at least two rotor units (4b, 5b) for magnetic bearing devices (4, 5) at two axially spaced locations of the rotor with the drum, by means of which the rotor with the drum can be held in suspension, is rotatably supportable and can be made to rotate within the housing in operation, b) wherein furthermore mutually spaced holders (I-4, I-5) having stator units (4a, 5a) of the bearing devices (4, 5) are formed on the frame, between which holders the housing of the separator insert is non-rotatably retained such that the rotor remains rotatable with the drum, c) wherein the relative position of the holders (I-4 and I-5) having the stator units (4a, 5a) of the bearing devices (4, 5) can be changed such that the separator insert can be exchanged, d) wherein the housing and at least one of the holders (I-4 and I-5) have corresponding interlocking elements in order to non-rotatably retain the housing on the holder.