In 2007 the IPP RF driven negative hydrogen ion source was chosen by the ITER board as the new reference source for the ITER neutral beam system. In order to support the design of the Neutral Beam Test Facility in Padua and its commissioning and operating phases, IPP is presently constructing a new test facility ELISE (Extraction from a Large Ion Source Experiment) for a large‐scale extraction from a half‐size ITER RF source. Plasma operation of up to one hour is foreseen; but due to the limits of the IPP HV system, pulsed extraction only is possible. The extraction system is designed for acceleration of negative ions of up to 60 kV. The start of the ELISE operation is planned for middle of 2010. The aim of the design of the ELISE source and extraction system was to be as close as possible to the ITER design; it has however some modifications allowing a better diagnostic access as well as more flexibility for exploring open questions. The design was also supported by diagnostics and modeling efforts of th...