<div class="htmlview paragraph">This paper describes the Thermal Balance test that has been performed on EuTEF (European Technology Exposure Facility) platform, to be flown in October 2007 as an attached payload of Columbus module to the ISS.</div> <div class="htmlview paragraph">The thermal control system of EuTEF is based on a passive concept, with several different payloads being each one a self-standing technological experiment, with a centralized power supply and data handling.</div> <div class="htmlview paragraph">Each instrument has its own TCS, independent one another: they are individually insulated by MLI. The test has been performed with EuTEF Flight Model (FM) on the Passive Attach System to have representative thermal flight-like interfaces.</div> <div class="htmlview paragraph">Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber (at INTESPACE, Toulouse-F) by means of a solar beam and a spin table suitably oriented to simulate a critical identified orbit, among all the possible on the ISS.</div> <div class="htmlview paragraph">EuTEF has been tested both in the operative mode (power dissipated is nearly 350W) and stay alive heaters mode. The un-powered transfer from the Shuttle cargo bay to the ISS has been tested as well. The main goals of the thermal balance test are discussed in detail, namely: <ul class="list disc"> <li class="list-item"><div class="htmlview paragraph">The definition of the steady-state temperatures for each instrument.</div></li> <li class="list-item"><div class="htmlview paragraph">The verification of the MLI efficiency.</div></li> <li class="list-item"><div class="htmlview paragraph">The testing of the cooling down time constant for the unpowered mode transfer phases</div></li> <li class="list-item"><div class="htmlview paragraph">The collection of data for test-model correlation.</div></li> </ul></div> <div class="htmlview paragraph">Overall test results have been excellent; EuTEF thermal control system thermal requested performance have been verified. EuTEF thermal interfaces have been confirmed as well.</div>