IEC 60230-2018 pdf download.Impulse tests on cables and their accessories.
This document defines the procedure for carrying out withstand lightning and switching impulse tests and withstand superimposed impulse test on cables and their accessories.
This document applies solely to the methods of carrying out the tests as such, independently of the problem of selecting the test levels to be specified. The voltages pertaining to the system on which cables and accessories are to be used are given in IEC 601 83 or in the relevant product standard.
This document specifies the following requirements:
• the characteristics and state of the test installation and those parts of the procedure which are common to withstand tests and tests above the withstand level;
• the procedure for carrying out withstand lightning and switching impulse tests and superimposed impulse test;
• the procedure for carrying out tests above the withstand level which is intended for research purposes.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60060-1 :201 0, High-voltage test techniques – Part 1: General definitions and test requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in the relevant product standards and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 superimposed impulse voltage
impulse voltage applied to a test object which is at the same time energized by a DC voltage
Note 1 to entry: The superimposed impulse voltage falls under the definition of composite voltage given in IEC 60060-1 :201 0, 9.2.
4 Characteristics of the test object to be subjected to the tests
The test object shall have been previously subjected to the test protocol as required by the relevant IEC product standards.If not specified in the reference IEC product standards, the following conditions shall be maintained:
• If the test object is not intended to include any other accessory, the length of the sample taken shall be such that the length of free cable between the terminations is at least 5 m.
• Where one joint is included in the test object, the minimum length of free cable, between the joint and terminations shall be 5 m. Where more than one joint is included, the same requirement shall be observed and in addition there shall be a minimum length of 3 m of free cable between successive joints.
5 State of the test object to be subjected to the test
The test object shall be maintained under the following conditions.
• Pressure conditions, if any: For gas-pressure and oil-filled cables, the pressure shall be adjusted in accordance with the relevant IEC standard.
• Temperature conditions:
The temperature conditions and the method of temperature measurement shall be as described in the relevant IEC standard, but other methods of temperature measurement may be used by agreement between the purchaser and the manufacturer.
6 Lightning impulse voltage
The peak voltage level of the lightning impulse is specified in the relevant product standard or contractual agreements. The lightning impulse voltage to be applied shall be a standard lightning-impulse voltage as specified in IEC 60060-1 with the exception that the front time T 1 shall be between 1 µs and 5 µs.
7 Switching impulse voltage
The peak voltage level of the switching impulse is specified in the relevant product standard.
The switching impulse voltage to be applied shall be a standard switching impulse voltage as specified in IEC 60060-1 .
8 Superimposed impulse voltage test
8.1 General
The superimposed impulse voltage test shall be carried out on HVDC cable systems. The peak voltage level of the switching impulse is specified in the relevant product standard.
When a superimposed impulse voltage test is required, Clause 8 shall be applied in addition to the other clauses of this document.
8.2 Test setup
Some possibilities are given to apply an impulse voltage to a test object which is at the same time energized by a DC voltage; Annex C illustrates the possible superimposed impulse test circuit arrangements.IEC 60230 pdf download.