Printed Circuit Boards Assembly (PCBAs) are regularly used in several electronics and technologies which make them very valuable devices. Defects or manufacturing faults within the printed circuit board production can cause failures in the final product with potentially catastrophic consequences in safety-critical fields. The testing phase of PCBAs is one of the most important stages because it determines the high quality of the final product. My thesis work, completely carried out in SPEA, a global leader company in testing, aimed to develop the testing of an avionics power supply board and the relative safety integration for the operator. Firstly, I had the possibility to closely see the state-of-the-art of SPEA tester, in particular the Flying Probe and 3030 Bed of Nails.