Overview
ISO/IEC 11801-1:2017/AMD1:2025 - Amendment 1 updates the international generic cabling standard for customer premises (Part 1: General requirements). This 2025 amendment incorporates the content of Corrigendum 1 (2025-12) and introduces balanced single pair cabling support (single-pair Ethernet, SPE) in addition to existing 4‑pair systems. It provides new component Categories and channel/link Classes for single-pair transmission, plus corrections and performance updates to the 2017 edition.
Key topics and technical requirements
- Single pair cabling Classes: Defines Classes T1-A, T1-B, and T1-C covering frequency ranges from 0.1 MHz up to 1 250 MHz (T1-A: to 20 MHz; T1-B: to 600 MHz; T1-C: to 1 250 MHz). T1-A is subdivided into sub-Classes (T1-A-100, T1-A-400, T1-A-1000) for different channel lengths.
- Channel and component performance: New transmission performance parameters (insertion loss, return loss, PS AACR-F, ELTCTL, delay/delay skew) and tables of informative key-frequency values. Return loss requirements and measurement guidance are specified for single-pair channels.
- Power delivery and DC resistance: Updated channel-level DC loop resistance limits (Table 17) and guidance for temperature correction of resistance; includes considerations for remote powering (S‑PoE / single pair Power over Ethernet).
- Crosstalk and shielding: New and revised requirements for alien crosstalk, coupling attenuation, and informative coupling attenuation values for screened channels.
- Normative references and connectors: Adds references relevant to single-pair cabling and testing (e.g., IEC 61156‑11/12/13/14 for single-pair cable specs, IEC 63171 connector standards, IEC 61935‑4 for installed single-pair testing).
- Environment and architecture: Notes distinct topologies and distribution architectures for single-pair deployments and points to MICE environmental classification and ISO/IEC TS 29125 for thermal/remote powering guidance.
Applications
- Intelligent building networks (sensors, actuators, controllers)
- Industrial automation and field devices requiring low‑pair count wiring
- Deployments needing data plus remote power over a single pair (S‑PoE / SPE)
- Cost- and space-sensitive installations where single-pair cabling is preferred
Who should use this standard
- Cabling system designers and specifiers
- Infrastructure installers and commissioning/test laboratories
- Network architects for smart buildings and industrial networks
- Cable and connector manufacturers developing SPE and S‑PoE products
- Facility managers and procurement teams specifying compliant cabling
Related standards (selected)
- IEC 61156‑11 / ‑12 / ‑13 / ‑14 - single pair cable sectional specifications
- IEC 63171 (connectors for single-pair data/power)
- IEC 61935‑4 - testing of installed single‑pair cabling
- ISO/IEC TS 29125 - cabling requirements for remote powering
Keywords: ISO/IEC 11801-1:2017/AMD1:2025, single pair cabling, single pair Ethernet, SPE, S‑PoE, generic cabling, channel performance, return loss, DC loop resistance, alien crosstalk, IEC 63171.