Enclosure with door for the assembly of distribution boards up to 250 A intended to be operated by ordinary persons according to IEC 61439-3. Open enclosure walls for the assembly or as single enclosure with closing plates. All insulated and made of high-quality polycarbonate. Quick enclosure connection with connectors and integrated gaskets. Large wall openings for the wiring. Cable entry via flanges. Wall fastening directly on enclosure, via external brackets or with mounting profile rails. Enclosure with fuse switch disconnector HRC 1, 3-pole, according to IEC 60947-3 on mounting plate. With incoming terminals, PE and N terminals. With connection for splitting-up incoming cables. Wiring area can be changed. With transparent door and door locking with tool operation.