Space radiation can affect performance of electronic components during a satellite's mission. In order to ensure reliable performance, these components must be tested under some types of radiation. Middle East Technical University-Defocusing Beam Line (METU-DBL) project aims to perform Single Event Effect (SEE) tests for space, HiLumi LHC, nuclear and other applications. ESA ESCC No. 25100 Standard Single Event Effect Test Method and Guidelines is considered for these SEE tests. Turkish Atomic Energy Authority (TAEA) has a cyclotron which can accelerate protons up to 30 MeV kinetic energy at the Proton Accelerator Facility (PAF) mainly for radioisotope production and for R&D purposes. According to the standard, the proton beam kinetic energy must be between 20 MeV and 200 MeV. While the proton energy is suitable for SEE tests, the beam size must be 15.40 cm x 21.55 cm and the flux must be between 10(5) p/cm(2)/s to at least 10(8) p/cm(2)/s according to the standard. The beam size at the entrance of the R&D room is mm-sized and the current is variable between 10 mu A and 1.2 mA. Therefore, a defocusing beam line has been designed to enlarge the beam size and reduce the flux. The beam line has three quadrupole magnets to enlarge the beam size and collimators and scattering foils are used for flux reduction. Currently, METU-DBL preliminary test setup, which was installed in the R&D room, enlarges the beam size with only two quadrupole magnets and it reduces the proton flux with a collimator. The final beam size is about 6 cm x 8 cm and the beam flux is similar to 10(9) p/cm(2)/s. The first tests of electronic components were performed and the commissioning results from the beam measurement system are here presented.