System having at least one master unit and a plurality of slave units, the master unit and the slave unit including means for performing communication via radio frequency channels. The at least one master unit includes means for transmitting control signals to the slave units, the slave units each being provided with a unique address and each being associated with a controllable device. The at least one master unit includes means for configuring the slave units addressable by the master unit in a number of sectors, and the master unit has further means for allocating predefined identifications to the slave units. Further, the master unit has display means, by means of which the predefined identifications may be displayed.