celduc group is a French electrical engineering and electronics company founded in 1964 by Michel Guichard. Headquartered near Saint-Etienne in the Rhône-Alpes region, France, the group is split into two specialized divisions: celduc transfo, focusing on transformers and magnetic components, and celduc relais, dedicated to solid state relays (SSRs). celduc transfo designs and manufactures custom transformers, inductors, and power supplies for industrial applications. celduc relais produces a comprehensive range of solid state relays, including single-phase, three-phase, compact, DIN rail, and PCB mount models. Product series include SO (compact SSRs), SC (control relays), S3 (three-phase SSRs), and SSR industrial relays, known for high reliability and long lifetime. The company serves global markets, with a strong presence in Europe, Asia, and the Americas. As the only French manufacturer of solid state relays, celduc holds a unique position in the European electronic components landscape. Its technology advantages include advanced thermal management, zero cross and random switching, and high immunity to electromagnetic interference. With decades of experience, celduc group is a trusted partner for automation, energy, and industrial equipment makers.