AS/NZS 4695.112:1996

1 - AS/NZS 4695.112:1996 FIRE HAZARD TESTING OF ELECTROTECHNICAL PRODUCTS - METHOD FOR DETERMINING THE COMPARATIVE AND THE...
4 - PREFACE
5 - CONTENTS
7 - 1. Scope
7 - 2. Definitions
7 - 2.1 Tracking
7 - 2.2 Electrical erosion
7 - 2.3 Comparative tracking index (CTI)
7 - 2.4 Proof tracking index (PTI)
8 - 3. Test specimen
8 - 4. Conditioning
8 - 5. Test apparatus
8 - 5.1 Electrodes
8 - 5.2 Test circuit
9 - 5.3 Dropping device
9 - 5.4 Test solutions
9 - 6. Procedure
9 - 6.1 General
10 - 6.2 Determination of the CTI
10 - 6.3 Proof tracking test
11 - 6.4 Determination of erosion
11 - 7. Report

Describes a method of test intended to indicate the relative resistance of solid electrical insulating materials to tracking for voltages up to 600 V when the surface is exposed, under electric stress, to water with the addition of contaminants. This Standard is identical with and has been reproduced from IEC 112:1979.

This method of test indicates the relative resistance of solid electrical insulating materials to tracking for voltages up to 600 V when the surface is exposed under electric stress to water with the addition of contaminants.Tracking may occur during this test when voltage is applied between a defined electrode arrangement on the surface of a material and drops of electrolyte are applied between them at defined intervals of time. The number of drops needed to cause failure increases with the reduction of the applied voltage and, below a critical value, tracking ceases to occur.Materials which do not track at the highest test voltage may erode differently. The depth of erosion can be measured. Some materials may ignite during the test.Notes 1. - The grading of materials reached by this method may possibly differ from that obtained by other testing methods for assessing tracking resistance, for example tests based on the use of high voltage, low-current discharges. This test method provides good resolution between materials with relatively poor tracking resistance. It lacks resolution for materials normally required for outdoor use for which the test method in IEC Publication 587: Test Method for Evaluating Resistance to Tracking and Erosion of Electrical Insulating Materials Used under Severe Ambient Conditions, should be used.2 . - The test results as such cannot be used directly for the evaluation of safe creepage distances when designing electrical apparatus.

First published in Australia as part of AS 2420-1980.
Second edition 1983.
Third edition 1987.
First published in New Zealand as part of AS 2420-1987.
Jointly revised and redesignated in part as AS/NZS 4695.112:1996.