Overview
IEC 61298-3:2026, published by the International Electrotechnical Commission (IEC), is an international standard that specifies general methods and procedures to evaluate the performance of process measurement and control devices with respect to the effects of influence quantities. This third edition provides updated methodologies for testing and documenting how various environmental and operational factors-such as temperature, humidity, vibration, and electrical disturbances-affect the functional characteristics of analogue and digital devices used in industrial process measurement and control. Process measurement transmitters (PMT) are now excluded from the scope and are covered by the IEC 62828 series.
This standard is applicable across a broad range of process instrumentation, supporting consistent, reliable evaluation for product development, quality control, procurement, and compliance.
Key Topics
Covered Influence Quantities
IEC 61298-3:2026 establishes methods for testing and reporting the impact on device performance from:
- Ambient temperature changes
- Ambient relative humidity
- Mechanical vibrations
- Shocks, drops, and tumbling
- Device mounting position
- Output load effects (electrical and pneumatic)
- Electrical supply variations (voltage, frequency, interruptions)
- Harmonic distortion and superimposed voltages
- Magnetic and electromagnetic fields
- Electrostatic discharge (ESD)
- Process fluid parameters (temperature, pressure, media flow)
- Atmospheric pressure changes
- Purge gas flow through devices
General Principles
- Device Characterization: Applies to devices identifiable by unique input/output variables and transfer functions.
- Test Applicability: Tests are performed only if relevant to the device under test; unnecessary tests can be excluded if justified.
- Reference Conditions: All tests are conducted with reference performance and environmental conditions as baseline.
- Reporting: All observed effects and deviations, particularly those impacting accuracy, linearity, hysteresis, and display functionality, are to be systematically documented.
Significant Updates in the 2026 Edition
- Removal of process measurement transmitters (PMT) from scope.
- Deletion of detailed EMC and electrical safety test content, retaining only references to relevant IEC standards.
Applications
IEC 61298-3:2026 supports a range of practical needs within process automation and instrumentation sectors:
- Manufacturers use the standard for consistent device evaluation, product development, and type approval.
- End-users (plant operators, engineers) rely on standardized test results for procurement decisions and lifecycle cost assessment.
- Testing laboratories gain a unified methodology for conducting influence quantity tests and preparing test reports across analogue and digital process devices.
- Regulatory bodies and compliance assessors reference the standard to verify that devices meet contractual and regulatory requirements.
Industries benefiting from IEC 61298-3 include chemical processing, food and beverage, power generation, oil and gas, pharmaceuticals, and water treatment-anywhere robust, repeatable performance of process measurement and control devices is critical.
Related Standards
For comprehensive evaluation and integration, IEC 61298-3:2026 references and works alongside several other international standards, including:
- IEC 61298-1:2026: General considerations for process measurement and control device performance evaluation
- IEC 61298-2:2026: Tests under reference conditions
- IEC 61298-4: Structure and content of performance evaluation reports
- IEC 60654 series: Operating conditions and influences for measurement and control equipment
- IEC 60068 series: Environmental testing methods for temperature, humidity, shock, and vibration
- IEC 61326-1: EMC requirements for measurement, control, and laboratory equipment
- IEC 62828 series: Specific to process measurement transmitters (PMT); not covered by IEC 61298-3
Summary
By adhering to IEC 61298-3:2026, stakeholders ensure that process measurement and control devices are rigorously evaluated for operational reliability under real-world environmental and electrical influence quantities. This standard underpins quality assurance, interoperability, and compliance in modern industrial automation and instrumentation.