A rotor device for a peristaltic pump containing a housing, a supporting shaft extending in an axial direction and being mounted in the housing, a rotor which contains a rotor-body mounted on the supporting shaft and extending in a radial direction from the supporting shaft and a plurality of rollers, mounted on the radially outer portion of the rotor-body and a driving device connected to the supporting shaft for driving the rotor, in which the peristaltic pump further contains a number of roller-markers corresponding to the number of rollers, in which the roller-markers indicate a dead zone, the roller-markers are provided directly or indirectly on the supporting shaft.