INSULATION COORDINATION FOR EQUIPMENT WITHIN LOW-VOLTAGE SYSTEMS - PART 1: PRINCIPLES, REQUIREMENTS AND TESTS
International Electrotechnical Committee
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
Describes 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.
| Document Type | Standard |
| Status | Current |
| Publisher | International Electrotechnical Committee |
| Committee | TC 109 |
| Supersedes |
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