IEC 60917-2-3:2006

Overview

IEC 60917-2-3:2006 is an extended detail specification within the IEC 60917 modular order for mechanical structures for electronic equipment. Focused on the 25 mm equipment practice, this part provides additional interface co‑ordination dimensions for subracks, chassis, backplanes, front panels and plug‑in units. It builds on IEC 60917-2-2 and aligns with cabinet/rack installation practice in IEC 60917-2-1. The publication covers mechanical interfaces for injector/extractor handles, electromagnetic shielding, key/coding and alignment systems, electrostatic discharge (ESD) provisions, and rear‑mounted plug‑in units. A bilingual (2013) edition corresponds to the original English text published in 2006.

Key Topics

• Subrack and plug‑in unit aperture dimensions - ensures front panels and plug‑in units meet standardized mounting interfaces for modular systems.
• Injector/extractor handle interfaces - standardized dimensions and locking functions for insertion and removal of plug‑in units.
• Electromagnetic shielding provisions - basic mechanical dimensions to support EMC/EMI enclosure requirements at the subrack and front panel level.
• Key/coding system - dimensions and programming guidance to prevent incorrect mating of plug‑in units (key positions, chambers and inspection dimensions).
• Alignment pins and receptacles - mechanical interface details for accurate module seating and optional electrical contacts on alignment pins.
• Electrostatic discharge (ESD) provisions - contact and strip interface dimensions to protect sensitive electronics during handling and insertion.
• Rear‑mounted plug‑in units - additional subrack and board dimensions for units that mount from the rear.
• Annex A connector guidance - examples for using metric connectors (references to IEC 61076 series) with the subrack/plug‑in geometry.

Applications

IEC 60917-2-3 is applied where robust, repeatable mechanical interfaces are required for modular electronic systems, including:

• Telecom and IT networking equipment enclosures and line cards
• Chassis and subrack manufacturers designing modular frames
• Backplane and PCB designers needing defined plug‑in unit envelope and connector locations
• System integrators managing cable mass, EMC layout and field‑serviceable modules
• Product teams implementing keying/coding, ESD and alignment strategies for high‑availability equipment

Who uses this standard

• Mechanical and enclosure designers
• Electromechanical engineers and hardware architects
• EMC/EMI engineers and compliance teams
• Rack and cabinet manufacturers
• Procurement and standards compliance teams in telecom/IT OEMs

Related Standards

• IEC 60917 (overall modular order series) - Parts 1, 2, 2-1, 2-2
• IEC 61076 series (metric connector specifications referenced in Annex A)

Use IEC 60917-2-3 when designing or specifying modular enclosures to ensure interoperability, safe insertion/removal, ESD protection and basic EMC provisions for subracks, plug‑in units, backplanes and front panels in 25 mm equipment practice.