The complexity of a smartgrid with a high percentage of renewable sources introduces several problems in testing equipment and power controls. In this context, real-time simulation and Hardware In the Loop (HIL) techniques can address these typical problems of electricity system testing. However, implementing an HIL configuration in a single infrastructure can be physically impossible or limiting. This paper introduces a platform called JaNDER that allows real-time data exchange between two or more infrastructures. This tool enables the integration of infrastructures, exploiting the synergies between them and creating a virtual infrastructure capable of running multiple experiments using a combination of the resources installed in each infrastructure. In particular, JaNDER can extend a HIL configuration. To validate this new testing concept, a centralized voltage controller was tested in a HIL configuration where JaNDER was used to interact with an On Load Tap Changer (OLTC) controller located in a remote infrastructure. The results show that the latency introduced by JaNDER is not high; therefore, under certain circumstances, JaNDER can be used to expand real-time testing without compromising the stability of the experiment.