IEC 60068-2-21:2021

Overview

IEC 60068-2-21:2021 is an International Electrotechnical Commission (IEC) standard focused on environmental testing, specifically Test U, which assesses the robustness of terminations and integral mounting devices in electrical and electronic components. This seventh edition supersedes the 2006 sixth edition and the withdrawn IEC 60068-2-77:1999, presenting significant technical revisions and integration for enhanced applicability.

The standard applies to all electrical and electronic components that have terminations or integral mounting devices susceptible to mechanical stresses during normal assembly or handling. It is also relevant for surface mount devices (SMDs). The primary objective is to ensure these components maintain structural and functional integrity under mechanical stresses such as axial, bending, torsion, and torque forces, enhancing reliability in practical applications.

Key Topics

• Test Ua: Robustness Against Axial Stresses
  Evaluates how terminals withstand tensile and thrust forces with specific preconditioning and measurement protocols to ensure they can endure axial mechanical stress during handling and assembly.

• Test Ub: Robustness Against Bending Stresses
  Covers the impact of bending forces on terminals, including pliable and rigid terminations. Methods include sequential bending tests designed to simulate real-world mechanical strain on leads and tags.

• Test Uc: Torsion
  Focuses on the ability of terminals to resist twisting forces. The test procedures involve specimen preparation, application of torsional moments, and subsequent measurements.

• Test Ud: Torque
  Examines threaded terminations or other configurations subject to torque. The standard specifies methods to test these components’ endurance under torque stresses related to fastening and mechanical operations.

• Test Ue: Robustness of SMD Terminations in the Mounted State
  Addresses surface mount devices’ resilience to mechanical stresses such as substrate bending, pull-off, push-off, and shear forces. This test ensures that SMD components reliably survive typical production and operational stresses.

• Test Uf: Robustness of Component Body
  Assesses component body strength and impact shock resistance, crucial for maintaining integrity during transportation and handling.

• Normative References and Specifications
  Includes relevant terminology, preconditioning steps, test methods, and measurement procedures. Annex X provides cross-references to previous editions and withdrawn standards for clarity.

Applications

IEC 60068-2-21:2021 is crucial for manufacturers, quality assurance teams, and test engineers involved with electrical and electronic components requiring mechanical robustness validation. Specific applications include:

• Component Design and Development
  Designing terminals and integral mounting devices that meet mechanical durability requirements.

• Quality Assurance and Compliance Testing
  Verifying that electrical and electronic components withstand mechanical stresses encountered during manufacturing, transportation, and operational use.

• Surface Mount Device (SMD) Assembly
  Ensuring SMD components adhere reliably to substrates and maintain electrical and mechanical performance.

• Reliability Assessment in Harsh Environments
  Testing components prone to mechanical handling stresses helps guarantee performance in demanding industrial, automotive, aerospace, and consumer electronics environments.

• Supplier and Vendor Qualification
  Specifying and verifying component robustness as part of the procurement process to ensure consistency and durability.

Related Standards

When implementing IEC 60068-2-21:2021, consider the following related standards to complement robustness testing and environmental qualification:

• IEC 60068 Series – A series of standards covering environmental testing for electrical and electronic equipment, including temperature, humidity, vibration, and shock tests.

• IEC 60068-2-77 – Previously separate standard for robustness of terminations, now integrated into IEC 60068-2-21.

• IEC 60999 – Standard concerning connection devices for electrical installations, relevant for termination provisions.

• ISO 9001 – Quality management principles that often align with testing requirements for manufacturing consistency.

• JEDEC and IPC Standards – Industry-specific norms for SMD handling and testing procedures.

Keywords: IEC 60068-2-21, environmental testing, robustness of terminations, integral mounting devices, mechanical stress testing, surface mount device (SMD) testing, axial stress, bending stress, torsion, torque testing, component reliability, electronic component durability, IEC standards, electrical testing protocols.