EN 60255-21-1:1995

Overview

EN 60255-21-1:1995 (CLC) specifies sinusoidal vibration tests for measuring relays and protection equipment. It is Part 21, Section 1 of the EN 60255 series covering vibration, shock, bump and seismic tests. The standard defines two type-test methods - the vibration response test and the vibration endurance test - and is generally based on the environmental test procedure EN 60068-2-6. Requirements apply only to equipment in a new condition and are intended for type testing to verify mechanical and functional performance under sinusoidal vibration.

Key Topics and Requirements

• Scope: Applies specifically to measuring relays and protection equipment; testing is for type approval rather than production inspection.
• Test types:
  • Vibration response test - assesses relay functional performance under specified sinusoidal vibration inputs.
  • Vibration endurance test - evaluates long-term mechanical and electrical durability under sustained vibration.
• Test basis: Test methods and principles are generally aligned with EN 60068-2-6 (sinusoidal vibration).
• Condition of equipment: Tests are defined for devices in a new (as-manufactured) condition.
• Sinusoidal vibration: The standard focuses on sinusoidal excitation (single-frequency sweep or dwell), rather than random vibration or shocks.

Applications

EN 60255-21-1 is used by professionals who need to demonstrate that relays and protection devices maintain accuracy, reliability and mechanical integrity when exposed to vibration in service environments:

• Relay and protection equipment manufacturers - for type testing new product designs and generating compliance data.
• Test laboratories - to perform standardized vibration response and endurance tests for certification reports.
• Utility and substation engineers - to specify ruggedness requirements for protective relays used in power systems.
• Component and enclosure designers - to validate mounting, damping and mechanical robustness against sinusoidal vibration.
• Quality and compliance teams - to ensure products meet applicable type-test standards before market release.

Related Standards

• EN 60068-2-6 - environmental testing: sinusoidal vibration (general test method referenced by this standard).
• Other parts of EN 60255-21 - sections addressing shock, bump and seismic tests for measuring relays and protection equipment.

Keywords: EN 60255-21-1, vibration tests, measuring relays, protection equipment, sinusoidal vibration, vibration response, vibration endurance, EN 60068-2-6, type tests, electrical relays.