Overview
ISO 15548-2:2013 - Non-destructive testing (NDT) - Equipment for eddy current examination - Part 2: Probe characteristics and verification defines how to describe, measure and verify the functional and electrical characteristics of eddy current probes and their interconnecting elements. The standard enables a well‑defined description and comparability of eddy current equipment so that a consistent and effective eddy current testing system can be designed for specific applications. It specifies measurement methods (using reference blocks and calibrated instruments) but does not set acceptance criteria or the extent of verification - those are provided in application documents.
Key topics and technical requirements
- Scope and purpose
- Identifies probe functional characteristics and interconnecting elements (cables, connectors, slip‑rings, rotating heads, transformers, multiplexers, amplifiers).
- Supports comparability and system design rather than prescribing pass/fail limits.
- Physical characteristics
- External size/shape, weight, mounting, housing material, facing, core/shield, orientation and electrical centre marks, model/serial numbers.
- Electrical characteristics
- Recommended excitation current/voltage and frequency ranges, impedance and resonant frequency of excitation elements, impedance of receiving elements; cable electrical characteristics.
- Measurement guidance using impedance meters, multimeters and appropriate test setups.
- Functional characteristics
- Directionality, response to elementary discontinuities (hole, slot), length/width/area of coverage, minimum detectable discontinuity for constant response, penetration and geometric effects, normalised impedance locus vs frequency.
- Requirements measured using calibration/reference blocks of suitable material.
- Verification framework
- Three verification levels: Level 1 (global functional check), Level 2 (detailed functional check and calibration), Level 3 (characterisation against manufacturer data).
- Verification procedures must specify which characteristics and intervals apply; corrective actions are required when performance drifts.
- Measurement conditions
- Measurements usually made at the probe connector with the probe in air and away from conductive/magnetic materials; instrumentation must be calibrated and reference blocks verified.
Applications and who uses it
- NDT engineers and inspectors performing eddy current testing (ECT)
- Probe and eddy‑current instrument manufacturers for design, specification and product data sheets
- Calibration laboratories and QA teams that verify probe performance
- Asset integrity and quality control organizations in aerospace, power generation, oil & gas, and manufacturing
ISO 15548-2 helps specify probe selection, enables reproducible verification and supports development of application‑specific inspection procedures.
Related standards
Using ISO 15548-2:2013 alongside related parts improves traceability, calibration practice and the reliability of eddy current testing programs. Keywords: ISO 15548-2, eddy current testing, probe characteristics, probe verification, NDT, impedance, reference blocks.