UNE-EN 60917-2-2
MODULAR ORDER FOR THE DEVELOPMENT OF MECHANICAL STRUCTURES FOR ELECTRONIC EQUIPMENT PRACTICES. PART 2: SECTIONAL SPECIFICATION. INTERFACE CO-ORDINATION DIMENSIONS FOR THE 25 MM EQUIPMENT PRACTICE. SECTION 2: DETAIL SPECIFICATION. DIMENSIONS FOR SUBRACKS, CHASSIS, BACKPLANES, FRONT PANELS AND PLUG-IN UNITS.