IEC 61051-1:2007

FOREWORD
1 General
  1.1 Scope
  1.2 Object
  1.3 Normative references
2 Technical data
  2.1 Units, symbols and terminology
  2.2 Terms and definitions
  2.3 Preferred values and characteristics
  2.4 Marking
       2.4.1 General
       2.4.2 Coding
3 Quality assessment procedures
  3.1 Qualification approval/quality assessment
       systems
  3.2 Primary stage of manufacture
  3.3 Structurally similar components
  3.4 Qualification approval procedures
  3.5 Quality conformance inspection
       3.5.1 Certified records of released lots
       3.5.2 Delayed delivery
       3.5.3 Release for delivery before the
              completion of Group B tests
  3.6 Alternative test methods
  3.7 Unchecked parameters
4 Test and measurement procedures
  4.1 General
  4.2 Standard atmospheric conditions
       4.2.1 Standard atmospheric conditions
              for testing
       4.2.2 Recovery conditions
       4.2.3 Referee conditions
       4.2.4 Reference conditions
  4.3 Drying and recovery
  4.4 Visual examination and check of dimensions
       4.4.1 Visual examination
       4.4.2 Marking
       4.4.3 Dimensions (gauging)
       4.4.4 Dimensions (detail)
  4.5 Nominal varistor voltage or leakage current
       (not applicable to pulse measurements)
       4.5.1 Test procedure
       4.5.2 Measurement and requirements
  4.6 Pulse current
       4.6.1 Standard pulse currents
       4.6.2 Tolerances
       4.6.3 Measurement of the pulse current
  4.7 Voltage under pulse condition
  4.8 Capacitance
  4.9 Voltage proof (for insulated varistors only)
       4.9.1 V-block method
       4.9.2 Metal ball method
       4.9.3 Foil method
  4.10 Insulation resistance (for insulated varistors
       only)
       4.10.1 Test procedure
       4.10.2 Measurement and requirements
  4.11 Robustness of terminations
       4.11.1 General
       4.11.2 Test Ua[1] - Tensile
       4.11.3 Test Ub - Bending (half of the number
              of terminations)
       4.11.4 Test Uc - Torsion (other half of the
              number of terminations)
       4.11.5 Test Ud - Torque (for terminations with
              threaded studs or screws and for integral
              mounting devices)
       4.11.6 Visual examination
       4.11.7 Final measurement
  4.12 Resistance to soldering heat
       4.12.1 Preconditioning
       4.12.2 Test procedure
       4.12.3 Recovery
       4.12.4 Final inspection, measurement and
              requirements
  4.13 Solderability
       4.13.1 Test procedure
       4.13.2 Final inspection, measurements and
              requirements
  4.14 Rapid change of temperature
       4.14.1 Initial measurement
       4.14.2 Test procedure
       4.14.3 Final inspection, measurement and
              requirements
  4.15 Bump
       4.15.1 Initial measurement
       4.15.2 Test procedure
       4.15.3 Final inspection, measurement and
              requirements
  4.16 Shock
       4.16.1 Initial measurement
       4.16.2 Test procedure
       4.16.3 Final inspection, measurement and
              requirements
  4.17 Vibration
       4.17.1 Initial measurement
       4.17.2 Test procedure
       4.17.3 Final inspection, measurement
              and requirements
  4.18 Climatic sequence
       4.18.1 Initial measurement
       4.18.2 Dry heat
       4.18.3 Damp heat, cyclic, Test Db, first cycle
       4.18.4 Cold
       4.18.5 Low air pressure
       4.18.6 Damp heat, cyclic, Test Db, remaining
              cycles
       4.18.7 Final inspection, measurement and
              requirements
  4.19 Damp heat, steady state
       4.19.1 Initial measurement
       4.19.2 Test procedure
       4.19.3 Final inspection, measurement and
              requirements
  4.20 Fire hazard
  4.21 Endurance at upper category temperature
  4.22 Solvent resistance of marking
       4.22.1 Test procedure
       4.22.2 Requirements
  4.23 Component solvent resistance
       4.23.1 Initial measurements
       4.23.2 Test procedure
       4.23.3 Measurement and requirements
  4.24 Mounting (for surface mount varistors only)
Annex A (normative) Mounting for measurements of
        varistors
Annex B (normative) Interpretation of sampling
        plans and procedures as described in
        IEC 60410 for use within the IEC quality
        assessment system for electronic components
Annex C (normative) Rules for the preparation of
        detail specifications for capacitors and
        resistors for electronic equipment

IEC 61051-1:2007 is applicable to varistors with symmetrical voltage current characteristics for use in electronic equipment. This second edition cancels and replaces the first edition published in 1991 and constitutes a minor revision related to tables, figures and references.