AS/NZS 61558.2.4:2001

1 - AS/NZS 61558.2.4:2001 SAFETY OF POWER TRANSFORMERS, POWER SUPPLY UNITS AND SIMILAR - PARTICULAR REQUIREMENTS FOR ISOLATING...
4 - CONTENTS
5 - PREFACE
7 - 1 Scope
7 - 2 Normative references
7 - 3 Definitions
8 - 4 General requirements
8 - 5 General notes on tests
8 - 6 Ratings
8 - 7 Classification
8 - 8 Marking and other information
9 - 9 Protection against accessibility to hazardous live parts
9 - 10 Change of input voltage setting
9 - 11 Output voltage and output current under load
9 - 12 No-load output voltage
10 - 13 Short-circuit voltage
10 - 14 Heating
10 - 15 Short-circuit and overload protection
10 - 16 Mechanical strength
10 - 17 Protection against harmful ingress of dust, solid objects and moisture
10 - 18 Insulation resistance and electric strength
11 - 19 Construction
12 - 20 Components
12 - 21 Internal wiring
12 - 22 Supply connection and other external flexible cable or cords
12 - 23 Terminals for external conductors
12 - 24 Provision for protective earthing
12 - 25 Screws and connections
13 - 26 Creepage distances, clearances and distances through insulation
13 - 27 Resistance to heat, abnormal heat, fire and tracking
13 - 28 Resistance to rusting
14 - Annexes
14 - Annex C - Material group II
14 - Annex D - Material group I
15 - Annex ZZ - Variations to IEC 61558-2-4:1997 for application in Australia and New Zealand

Specifies general safety requirements for approval and test purposes for isolating transformers for general use. This Standard is an adotpion with national modifications and contains the full text of IEC 61558-2-4:1997.

Replacement:This part 2 of IEC 61558 AS/NZS 61558 applies to stationary or portable, single-phase or polyphase, air-cooled isolating transformers, associated or otherwise, having a rated supply voltage not exceeding 1000 V a.c. and rated frequency not exceeding 500 Hz, the rated output not exceeding:– 25 kVA for single-phase transformers;– 40 kVA for polyphase transformers.This standard is also applicable to isolating transformers without limitation of the rated output, however such transformers are considered as special transformers and are subjected to an agreement between the purchaser and the supplier.The no-load output voltage or the rated output voltage does not exceed 500 V a.c. or 708 V ripple-free d.c.NOTES1 The no-load output voltage or the rated output voltage may be up to 1 000 V a.c. or 1 415 V ripple-free d.c. to be in accordance with the national wiring rules or for a special purpose.2 This standard is applicable to those isolating transformers used when the installation rules call for the separation of circuits for the supply of certain parts of the circuits or of equipment (portable tools, lawn mowers, etc.).The no-load output voltage and/or the rated output voltage shall exceed 50 V a.c. and/or 120 V ripple-free d.c.This standard is also applicable to transformers associated with specific items of equipment, to the extent decided upon by the relevant IEC technical committees.This standard is applicable to dry type transformers. The windings may be encapsulated or non-encapsulated.NOTES3 For transformers filled with liquid dielectric or pulverized material, such as sand, additional requirements are under consideration.4 In locations where special environmental conditions prevail, particular requirements may be necessary in accordance with IEC 60364-5-51.

AS 3108 first published in Australia in part as AS C126-1939.
Second edition 1958.
AS C167 first published 1962.
Revised and redesignated AS 3167-1981 (withdrawn 1987).
AS C126-1958 revised and redesignated AS 3126-1981 (withdrawn 1989).
AS 3126-1981 and AS 3167-1981 were revised and redesignated AS 3108.1-1984, AS 3108.2-1984 and AS 3108.3-1984.
Revised, amalgamated and redesignated AS 3108-1990.
First published in New Zealand as NZS/AS 3108:1990.
Jointly revised and designated as Joint Standard AS/NZS 3108:1994.
Jointly revised and redesignated in part as AS/NZS 61558.2.4:2001.