An important application for the SIMOREG CM converter is in the retrofitting and modernization of DC drives in existing systems. In the field of DC drives, many systems exist that are older than 5 or 10 years and that still use analog technology. On retrofitting or updating these systems, the motor, mechanical components and power section are retained and only the closed-loop control section is replaced by a 6RA70 Control Module. This is an extremely economical way to obtain a modern DC drive with the complete functional scope of the well-proven, fully digital converters of the SIMOREG DC MASTER series.It is easily adapted to the configuration of the existing components by setting parameters.