There are a number of substantial changes in the 3rd Edition of IEC 60601-1 and this paper focuses on one of these changes, the introduction of the concept of MOOPs and MOPPs. In order to ease the design in of a suitable power supply, Excelsys now offers the Xgen with 2 x MOPPs as standard. This paper will focus on one of the high visibility changes between the second and third edition of the IEC 60601-1, the introduction of MOOPs and MOPPs.