IEC 60664-1:2007

1 Scope and object
2 Normative references
3 Terms and definitions
4 Basis for insulation coordination
  4.1 General
  4.2 Insulation coordination with regard to voltage
      4.2.1 General
      4.2.2 Insulation coordination with regard to long-term
            a.c. or d.c. voltages
      4.2.3 Insulation coordination with regard to transient
            overvoltage
      4.2.4 Insulation coordination with regard to recurring
            peak voltage
      4.2.5 Insulation coordination with regard to temporary
            overvoltage
      4.2.6 Insulation coordination with regard to environmental
            conditions
  4.3 Voltages and voltage ratings
      4.3.1 General
      4.3.2 Determination of voltage for long-term stresses
      4.3.3 Determination of rated impulse voltage
      4.3.4 Determination of recurring peak voltage
      4.3.5 Determination of temporary overvoltage
  4.4 Frequency
  4.5 Time under voltage stress
  4.6 Pollution
      4.6.1 General
      4.6.2 Degrees of pollution in the micro-environment
      4.6.3 Conditions of conductive pollution
  4.7 Information supplied with the equipment
  4.8 Insulating material
      4.8.1 Comparative tracking index (CTI)
      4.8.2 Electric strength characteristics
      4.8.3 Thermal characteristics
      4.8.4 Mechanical and chemical characteristics
5 Requirements and dimensioning rules
  5.1 Dimensioning of clearances
      5.1.1 General
      5.1.2 Dimensioning criteria
      5.1.3 Electric field conditions
      5.1.4 Altitude
      5.1.5 Dimensioning of clearances of functional insulation
      5.1.6 Dimensioning of clearances of basic, supplementary
            and reinforced insulation
      5.1.7 Isolating distances
  5.2 Dimensioning of creepage distances
      5.2.1 General
      5.2.2 Influencing factors
      5.2.3 Dimensioning of creepage distances of functional
            insulation
      5.2.4 Dimensioning of creepage distances of basic,
            supplementary and reinforced insulation
      5.2.5 Reduction of creepage distances with the use of
            a rib (ribs)
  5.3 Requirements for design of solid insulation
      5.3.1 General
      5.3.2 Stresses
      5.3.3 Requirements
6 Tests and measurements
  6.1 Tests
      6.1.1 General
      6.1.2 Test for verification of clearances
      6.1.3 Tests for the verification of solid insulation
      6.1.4 Performing dielectric tests on complete equipment
      6.1.5 Other tests
      6.1.6 Measurement accuracy of test parameters
  6.2 Measurement of creepage distances and clearances
Annex A (informative) Basic data on withstand characteristics
                      of clearances
Annex B (informative) Nominal voltages of supply systems for
                      different modes of overvoltage control
Annex C (normative) Partial discharge test methods
Annex D (informative) Additional information on partial
                      discharge test methods
Annex E (informative) Comparison of creepage distances
                      specified in Table F.4 and clearances
                      in Table A.1
Annex F (normative) Tables
Bibliography

IEC 60664-1:2007 Deals with insulation coordination for equipment within low-voltage systems. It applies to equipment for use up to 2 000 m above sea level having a rated voltage up to a.c. 1 000 V with rated frequencies up to 30 kHz, or a rated voltage up to d.c. 1 500 V. It specifies the requirements for clearances, creepage distances and solid insulation for equipment based upon their performance criteria. It includes methods of electric testing with respect to insulation coordination. The minimum clearances specified in this standard do not apply where ionized gases occur. Special requirements for such situations may be specified at the discretion of the relevant technical committee. This standard does not deal with distances:
- through liquid insulation,
- through gases other than air,
- through compressed air.
Main changes have been made with respect to the previous edition:
- Amendment of Japanese mains conditions with regard to the rated impulse voltages, the rationalized voltages and the nominal voltages of supply systems for different modes of overvoltage control
- Amendment of dimensioning of clearances smaller than 0,01 mm
- Alignment of the table and the corresponding formula regarding test voltages for verifying clearances at different altitudes
- Amendment of interpolation of the creepage distance values for functional insulation
- Amendment of creepage distance dimensioning taking into account ribs
- Revision of the former Clause 4 "Tests and measurements" (now Clause 6) to achieve a more detailed description of the tests and their purpose, the test equipment and possible alternatives
- Change of Annex C "Partial discharge test methods" from a former technical report, Type 2 (now called TS), to a normative Annex C.