IEC 60068-2-2:2007

Overview

IEC 60068-2-2:2007 is an international standard developed by the International Electrotechnical Commission (IEC) that defines environmental testing methods specifically for dry heat exposure. It is part of the broader IEC 60068 series concerning environmental testing of electrical, electronic, and related equipment.

This standard outlines test procedures focused on determining the ability of components, equipment, or articles to withstand high temperature conditions during storage, transportation, or usage. Importantly, it targets tests with gradually applied dry heat to both heat-dissipating and non heat-dissipating specimens, ensuring their reliability and durability in elevated temperature environments.

IEC 60068-2-2:2007 excludes assessment of temperature variation tolerance; such assessments fall under IEC 60068-2-14 (Test N: Change of Temperature). The dry heat test emphasizes evaluation under stable, controlled thermal conditions, reflecting real-world operational or storage scenarios where high temperature endurance is critical.

Key Topics

• Test Categories:

  • Test Bb: Dry heat for non heat-dissipating specimens with gradual temperature change
  • Test Bd: Dry heat for heat-dissipating specimens with gradual temperature change (specimens unpowered during conditioning)
  • Test Be: Dry heat for heat-dissipating specimens with gradual temperature change, powered throughout the test

• Scope and Objectives:

  • Assess endurance of specimens against long-term exposure to dry heat
  • Evaluate suitability for transport, storage, and operation at high temperatures
  • Exclude rapid temperature cycling or shock evaluation

• Test Conditions and Parameters:

  • Gradual temperature increase to avoid thermal shock
  • Air velocity control inside test chambers (low or high velocity depending on specimen type)
  • Specimen temperature monitoring to confirm stability and uniform heat application
  • Power supply requirements for heat-dissipating specimens during testing

• Changes from Previous Editions:

  • Removal of Tests Ba and Bc due to severity overlap with Test Nb (IEC 60068-2-14)
  • Elimination of 3% limit on temperature differences between chamber air and wall temperature
  • Increased focus on powering specimens continuously during test where applicable
  • Removal of annexes to streamline test procedures

Applications

IEC 60068-2-2:2007 is widely used in industries requiring assurance that devices and components can endure elevated temperatures without degradation. Common applications include:

• Electrical and Electronic Equipment Testing
  Manufacturers use this standard to qualify products such as circuits, sensors, transformers, and other electronic assemblies that may experience harsh thermal environments.

• Component Reliability Verification
  Ensuring that non heat-dissipating items like resistors, capacitors, and connectors maintain integrity and function when exposed to heat during shipping or in service.

• Heat-Dissipating Device Endurance
  Testing powered equipment such as power supplies and heat-generating devices to verify performance under prolonged heat exposure, critical for consumer electronics, automotive systems, and industrial control units.

• Transport and Storage Validation
  Assessing packaging and product robustness when subjected to elevated temperatures in transit or storage, enhancing product lifecycle and reducing failure rates.

• Quality Control and Certification
  Providing a standardized basis for compliance with international market requirements and safety certifications related to thermal endurance.

Related Standards

IEC 60068-2-2:2007 is part of a comprehensive suite of environmental testing standards addressing different conditions and stressors:

• IEC 60068-2-14: Change of Temperature (Test N)
  Complementary to dry heat testing, this evaluates specimen ability to handle rapid temperature fluctuations and thermal cycling.

• IEC 60068-1: General and Guidance
  Provides overarching principles and terminology used across environmental test methods.

• IEC 60068-3-1 and IEC 60068-3-5: Supporting Documentation and Guidance
  Offers background information and confirmation procedures for temperature test chambers, ensuring reliable test environments.

• IEC 60068-5-2: Guide to Drafting of Test Methods
  Key for understanding test definitions, conditions, and terminology that impact applicability and interpretation of results.

• IEC 60721 Series: Classification of Environmental Conditions
  Provides classifications and descriptions of environmental conditions relevant for selecting appropriate test methods.

Keywords: IEC 60068-2-2, dry heat test, environmental testing, heat-dissipating specimens, non heat-dissipating specimens, temperature stability, electrical equipment testing, electronic components, thermal endurance, international standard, IEC environmental tests.