SystemC is a discrete event simulator that enables the programmer to model complex designs with varying levels of abstraction. In order to improve precision, it can be coupled to more specialized simulators. This article introduces the concept of loose simulator coupling between an analogue simulator and SystemC. It explains the properties and advantages which include a higher simulation performance as well as a higher degree of flexibility. A design example in which SystemC will be connected to SwitcherCad will demonstrate the benefits of loose coupling.