Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
IEC TR 62225: Guidance on Terms for Connectors and Mechanical Structures in Electronic Equipment
IEC TR 62225 (First Edition, 2001) is a technical report providing harmonized guidance on terminology used in the field of connectors and mechanical structures for electronic equipment. Prepared by IEC Technical Committee TC 48 (Electromechanical Components and Mechanical Structures for Electronic Equipment), this document compiles a comprehensive list of preferred terms collected from published standards and ongoing projects, serving as an essential reference for standardization authors, design engineers, and technical writers.
💡 Purpose: This technical report is not a vocabulary in the traditional sense. Instead, it offers project leaders and standard authors a preferred selection of terms for use in new publications, enabling significant shortening of the terms-and-definitions clauses that form part of most standards.
1. 📋 Scope and Organization
The report covers terminology primarily used in IEC publications under the responsibility of TC 48. Terms are organized alphabetically from A to Z, with each entry providing a description, source reference (the publication or project where the term was used), status classification, and application recommendation. The status system uses several categories:
| Status | Meaning | Example Use Case |
|---|---|---|
| Published | Term has been published in an IEC document | Standardized terms for general use |
| Modified | Deviates from a previously published term | Updated definitions reflecting new technology |
| Deprecated | Replaced by a better term | Phasing out ambiguous terminology |
| Obsolete | No longer in use | Historical terms for reference only |
| Draft | Part of a document currently in preparation | Emerging terminology under development |
| Unique | Fully new term not used in any prior document | Novel concepts requiring standardization |
| Superseded | Superseded by another published term | Terminology replaced by more precise alternatives |
2. 🔧 Key Terminology Areas
2.1 Connector Types and Components
The report covers a vast array of connector-related terms, from basic concepts like contact, terminal, and housing to specialized connectors such as coaxial connectors, ribbon cable connectors, and insulation displacement connectors (IDC). Each term includes precise dimensional and functional definitions to eliminate ambiguity in specifications.
2.2 Mechanical Structures
Terms related to mechanical structures include subrack, chassis, backplane, front panel, plug-in unit, and their associated dimensional coordination as defined in the IEC 60917 series. These terms are essential for ensuring mechanical interoperability between components from different manufacturers.
2.3 Connection Techniques
The document addresses various connection technologies with standardized terminology:
- Crimped connections (IEC 60352-2) — permanent connections formed by compressing a contact barrel around a conductor
- Insulation displacement connections (IDC) (IEC 60352-3, -4) — connections made by displacing insulation to establish contact with the conductor
- Spring clamp connections (IEC 60352-7) — tool-less connections using spring force to maintain contact pressure
- Screw-type terminals (IEC 60999-1) — traditional clamped connections using threaded fasteners
⚠️ Terminology Trap: The term “solderless connection” is often misunderstood. It does NOT mean “no mechanical connection” — rather, it refers to connections achieved through mechanical deformation (crimping, IDC, spring clamp) without the use of solder. Engineers should be careful not to conflate “solderless” with “less reliable.” Properly executed crimped connections often exceed soldered connections in mechanical strength and vibrational resistance.
3. 🔬 Engineering Application and Best Practices
3.1 Using Standardized Terminology in Design Specifications
The report emphasizes the importance of adopting standardized terminology in design specifications and procurement documents. When a designer specifies a “plug-in unit” rather than a vague “card” or “board,” they invoke a whole system of dimensional and interface standards (IEC 60917-2-2) that guarantee mechanical compatibility.
3.2 Interfacing with IEC 60050-581
Terms published in IEC 60050-581 (IEV Chapter 581: Electromechanical Components for Electronic Equipment) are listed “for information” in the report. The key difference is that while the IEV provides a general vocabulary, IEC TR 62225 offers practical recommendations on which terms to use and how to apply them, including status indicators showing whether a term is preferred, deprecated, or superseded.
3.3 Impact on International Trade
Standardized terminology reduces technical barriers to trade. When manufacturers in different countries use the same precisely defined terms for connector characteristics (e.g., contact resistance, withdrawal force, durability class), product specifications become unambiguous, enabling global sourcing and interoperability.
✅ Engineering Best Practice: When writing a new product specification or standard, always consult IEC TR 62225 first for preferred terminology. Using terms marked with “Published” or “Unique” status ensures your documentation aligns with international usage. Avoid “Deprecated” or “Obsolete” terms even if they appear in older company documentation. This practice dramatically reduces misinterpretation in global supply chains.
4. ❓ Frequently Asked Questions
Q1: Is IEC TR 62225 a mandatory standard or a guidance document?
It is a Technical Report — purely informative and not intended to be regarded as an International Standard. However, following its terminology recommendations is strongly encouraged for new and revised standards to maintain consistency across the IEC publication portfolio.
Q2: How does this report differ from IEC 60050-581 (IEV)?
IEC 60050-581 is the official IEV chapter for electromechanical components, providing standardized definitions. IEC TR 62225 goes further by offering status classifications, application recommendations, and source references, making it a practical guide for standards authors rather than just a reference vocabulary.
Q3: Can I use terms from this report in commercial product documentation?
Absolutely. In fact, using standardized terminology from IEC publications in product datasheets, manuals, and marketing materials improves clarity and demonstrates compliance with international engineering practices, which is particularly valuable for export-oriented manufacturers.
