IEC 61935-1:2015

Overview

IEC 61935-1:2015 specifies reference measurement procedures and field tester accuracy requirements for installed balanced information‑technology cabling as defined in ISO/IEC 11801 and equivalent cabling standards. It provides guidance for laboratory and field verification of electrical cabling parameters and applies when cable assemblies use cables complying with the IEC 61156 family and connecting hardware specified in the IEC 60603‑7 family or related IEC 61076 connector standards. This 2015 edition extends the upper test frequency to 1 000 MHz, adds standardized tests for exogenous (alien) crosstalk, and introduces Annex A covering uncertainty and variability of field test results.

Key topics and requirements

• Reference measurement procedures for electrical properties - defines how to measure and report key parameters using calibrated equipment (e.g., network analysers).
• Field tester accuracy - minimum accuracy and calibration requirements for portable testers used in acceptance and verification testing.
• Measured parameters (examples covered):
  • Insertion loss (attenuation)
  • Propagation delay and delay skew
  • Near‑end crosstalk (NEXT) and power‑sum NEXT
  • Far‑end crosstalk (FEXT), ACR‑N and ACR‑F
  • Return loss
  • DC loop resistance and resistance unbalance
  • Unbalance attenuation and coupling attenuation
  • Power‑sum alien crosstalk (PS ANEXT) and PS AACR‑F (exogenous crosstalk)
• Test configurations and setups - termination methods, balun and test lead requirements, coaxial vs balanced measurements.
• Reporting and uncertainty - standard formats for test reports and Annex A guidance on variability and measurement uncertainty.

Practical applications and users

IEC 61935‑1 is used for:

• Acceptance testing and certification of structured cabling installations (offices, data centres, industrial networks).
• Installation verification and quality assurance by cabling contractors and installation engineers.
• Troubleshooting and performance validation by network operations and maintenance teams.
• Product and component testing by manufacturers and test laboratories to verify compliance with cabling specifications.
• Procurement and contract specifications, ensuring test criteria and field‑tester accuracy are clearly defined.

Typical users: cabling installers, test technicians, system integrators, data centre operators, telecommunications engineers, certification labs, and standards/compliance professionals.

Related standards

• ISO/IEC 11801 (structured cabling specifications)
• IEC 61156 (cable construction standards)
• IEC 60603‑7 and IEC 61076 series (connector standards)

Keywords: IEC 61935-1, cabling testing, balanced cabling, field tester accuracy, alien crosstalk, ISO/IEC 11801, IEC 61156, structured cabling testing, data center cabling.