Overview
ISO/IEC TS 29125:2017 - Information technology - Telecommunications cabling requirements for remote powering of terminal equipment - provides guidance on using generic balanced cabling (as defined in the ISO/IEC 11801 series) to deliver remote power to terminal equipment across customer premises. The technical specification covers both new cabling installations and renovations, and applies where cabling may be installed before the selection of remote powering or powered devices.
Key topics and requirements
- Cabling types supported: Requirements for 4‑pair balanced cabling and 1‑pair balanced cabling used for remote powering.
- Installation conditions: Guidance on ambient temperature, installation near equipment, cable bundling, conduit vs. air installations, and administrative considerations.
- Temperature rise and current capacity: Methods and limits for modelling and measuring temperature rise in cable bundles, factors affecting heating, and how bundle size and layout impact conductor current capacity.
- Remote power delivery methods: Examples and topologies including end‑point powering, mid‑span powering and single‑pair remote powering; considerations for using signal pairs versus spare pairs.
- Transmission parameters: DC loop resistance, DC resistance unbalance (within pair and pair‑to‑pair), and maximum loop resistance for channels used for powering.
- Connecting hardware: Requirements for connectors and connecting hardware for both 4‑pair and 1‑pair remote powering implementations.
- Testing and validation: Informative annexes include modelling approaches, test protocols, detailed test procedures, and illustrative figures/tables to evaluate heating and compliance.
Practical applications
ISO/IEC TS 29125 is practical for anyone planning, installing or specifying cabling that will carry power in addition to data. Typical uses:
- Designing building cabling for remote powering of IP phones, wireless access points, security cameras or IoT devices (where remote powering topologies apply).
- Specifying cable types and bundle practices to ensure safe current capacity and acceptable temperature rise.
- Creating installation and test procedures to validate remote powering deployments and meet safety/performance targets.
- Assessing retrofit/renovation scenarios where cabling may be installed before the final choice of powered equipment.
Who should use this standard
- Network designers and cabling consultants
- Electrical and telecom installers
- Facilities and data center managers
- Specifiers, procurement teams, and standards compliance officers
- Manufacturers of cabling products and connecting hardware
Related standards
- ISO/IEC 11801 series (generic cabling for customer premises) - primary cabling framework referenced by ISO/IEC TS 29125.
Keywords: ISO/IEC TS 29125, remote powering, telecommunications cabling, balanced cabling, 4‑pair, 1‑pair, temperature rise, DC loop resistance, ISO/IEC 11801.