The invention relates to a module arrangement (1) with a base module and at least one submodule (5); the base module has at least two connection modules. The submodule (5) can be put into contact via a connection module with a choice of one of the connection modules of the base module and can consequently be attached to the base module in different orientations. Detection devices for detecting the orientation of the submodule (5) attached to the base module are provided in the base module.