IEC 61196-1-114:2025

Overview

IEC 61196-1-114:2025 - "Coaxial communication cables - Part 1-114: Electrical test methods - Test for inductance" is the second edition (2025) of the IEC test method for determining inductance characteristics of coaxial communication cables. It cancels and replaces the 2015 edition and includes technical revisions to terminology, test-sample layout, measuring procedures and adds guidance on the bending effect (Annex A).

Key topics and requirements

• Scope: Defines a standardised test method to measure the inductance of coaxial cables used in communications.
• Edition changes: Revision of the term inductance, addition of an abbreviated term (CUT - cable under test), revised sample length and layout, updated measuring procedure, and Annex A on bending effects.
• Test equipment: Measurements may be made with an impedance analyser, LCR‑meter, or impedance bridge (Wheatstone, Maxwell). Required measurement accuracy is ≤ 2%.
• Test sample: Minimum sample length: 10 m. For higher frequencies, shorter delivery lengths are permitted if less than 1/20 of the signal wavelength. Sample can be straight or bent (bending radius > minimum allowed; no closed loops).
• Calibration: Calibrate the setup (open, short, load) and measure the influence of connecting cables at the test frequency; save calibration data for correction.
• Test setup & procedure: Measure input impedance Z of the CUT with a short circuit at the far end. LCR meters and impedance analysers often display inductance directly. Formulae and per‑unit‑length conversions are provided for deriving L from dimensions where applicable.
• Normalization and reporting: Results are normalized to a reference length of 1 km. Test reports must record test conditions and corrected values, including temperature, test frequency, sample length, normalized inductance (mH/km), and equipment used.
• Annex A - bending effect: Analytical and experimental guidance showing that for relatively long cables at low frequencies the bending effect on inductance is negligible; line‑current and circuit models are provided for twinaxial and coaxial cables.

Applications and users

This standard is used by:

• Cable manufacturers for routine electrical verification and quality control of coaxial communication cables.
• Test laboratories and certification bodies performing inductance measurements as part of product specifications.
• Designers and R&D teams validating cable models and ensuring consistency with system impedance and electromagnetic performance.
• Procurement and compliance teams specifying test procedures in tender or regulatory documents.

Practical benefits include consistent inductance measurement, clear calibration and reporting practices, and guidance that reduces uncertainty when testing long or bent cable samples.

Related standards

• IEC 61196-1: Generic specification - general definitions and requirements for coaxial cables
• IEC 61196-1-101: Electrical test methods - conductor DC resistance
• IEC 60811-1-1: referenced for dimensional measurement used in inductance calculations

Keywords: IEC 61196-1-114:2025, coaxial communication cables, inductance test, electrical test methods, impedance analyser, LCR‑meter, bending effect, inductance measurement, cable testing.