The D0 fuse system is used in low-voltage systems in which the fuse inserts are accessible to laymen and can be replaced by them. It is the most modern screw fuse system and is designed for 400VAC/250VDC. The sizes D01, D02 and D03 make up the D0 system. D0 fuse bases are used together with D0 fuse inserts to protect cables and systems. D0 fuse inserts safely switch off impermissible overcurrents and short-circuit currents up to the nominal breaking current. They also protect electrical devices and systems from the electrodynamic effect of high short-circuit currents. DIN VDE 0636-3, DIN EN 60743. With this special retaining spring you can insert D02 fuses in D03 fuse bases.