Overview
IEC 61326-2-1:2020 (Edition 3.0) is a Part 2 supplement to IEC 61326-1:2020 that defines EMC test configurations, operational conditions and performance criteria specifically for sensitive test and measurement equipment that is intentionally EMC unprotected for functional reasons. It applies to instruments with internal or external test and measurement circuits - for example oscilloscopes, logic analysers, spectrum/network analysers, analogue instruments, digital multimeters (DMM) and board test systems. The manufacturer is responsible for specifying the intended environment and selecting the appropriate test levels from IEC 61326-1:2020.
Key Topics and Requirements
- Test configuration and EUT setup
- Test and measurement input ports should be capped/covered and terminated with appropriate impedance unless doing so would create an unrepresentative operating condition.
- Output ports not required for essential functions should be capped/terminated.
- Electrostatic discharge (ESD) is applied to housing shields or connector shields - not to inner pins of shielded connectors.
- Operational conditions during testing
- Both battery and AC mains modes must be tested when both are available.
- Specific guidance for common instruments:
- Oscilloscopes: maximum sweep speed, maximum sensitivity, continuous acquisition.
- Logic analysers: data analysis modes for emissions, continuous acquisition for immunity.
- DMMs: peak detect, maximum sensitivity (auto-range), continuous acquisition.
- For other equipment, representative worst‑case normal-operation modes are selected.
- Immunity and performance criteria
- Applies IEC 61326-1 immunity tests with specified additions.
- For transient electromagnetic phenomena assigned to performance criterion B, temporary self-recovering degradation is allowed; manufacturer must document any self-recovery times greater than 10 s. No change of operating state or loss of stored data is permitted.
- Documentation and user instructions
- Manufacturers must inform users that connecting test leads/probes may reduce immunity and provide guidance to minimize disturbance impact.
Applications and Who Uses It
- Intended for manufacturers, test engineers and EMC compliance teams working with laboratory and production test instruments that are sensitive by design and not EMC-hardened.
- Useful for designers of oscilloscopes, logic analysers, DMMs and board test systems; test laboratories developing EMC test plans for unprotected measurement equipment; and procurement/specification engineers assessing suitability of sensitive instruments for specific electromagnetic environments.
Related Standards
- IEC 61326-1:2020 - General EMC requirements for measurement, control and laboratory equipment (to be used in conjunction with Part 2-1).
- IEC 60050-161 - Electrotechnical vocabulary (terms and definitions referenced).
Keywords: IEC 61326-2-1, EMC requirements, test configurations, immunity testing, emissions, sensitive test and measurement equipment, oscilloscopes, logic analysers, DMM, manufacturer instructions.