BS EN 60137:2017 pdf download.Insulated bushings for alternating voltages above 1000 V.
BS EN 60137 specifies the characteristics and tests for insulated bushings.
This standard is applicable to bushings, as defined in Clause 3. intended for use in electrical apparatus, machinery, transformers. switchgear and installations for three-phase alternating current systems, having highest voltage for equipment above 1 000 V and power frequencies of 15 Hz up to and including 60 Hz.
Subject to special agreement between purchaser and supplier, this standard may be applied,
in part or as a whole, to the following:
• bushings used in other than three-phase systems:
• bushings for high-voltage direct current systems;
• bushings for testing transformers:
• bushings for capacitors.
Special requirements and tests for transformer bushings in this standard apply also to reactor bushings.
This standard is applicable to bushings made and sold separately. Bushings which are a part of an apparatus and which cannot be tested according to this standard should be tested with the apparatus of which they form part.
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 60038, IEC standard voltages
IEC 60050-212:2010, International Electrotechnical Vocabulary — Part 212: Electrical insulating solids, liquids and gases
IEC 60059, IEC standard current ratings
IEC 60060-1, High-voltage test techniques — Part 1: General definitions and test requirements
IEC 60068-2-17:1994, Basic environmental testing procedures — Part 2-17: Tests — Test Q: Sealing
IEC 60071-1, Insulation co-ordination — Part 1: Definitions, principles and rules IEC 60076-5, Power transformers — Part 5: Ability to withstand short circuit
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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 bushing
device that enables one or several conductors to pass through a partition such as a wall or a tank, and insulates the conductors from it; the means of attachment (flange or fixing device) to the partition forms part of the bushing
Note I to entry: The conductor may form an ntegral part of the bushing or be drawn nIo the central tube of the bushing.
[SOURCE: IEC 60050-471:2007, 471-02-01J
3.2 liquid-filled bushing
bushing in which the space between the inside surface of the insulating envelope and the solid major insulation is filled with mineral oil or other insulating liquid
3.3 compound-filled bushing
bushing in which the space between the inside surface of the insulating envelope and the solid major insulation is filled with an insulating compound
3.4 liquid-Insulated bushing
bushing in which the major insulation consists of mineral oil or another insulating liquid, enclosed by an insulating envelope
4 Ratings
4.1 Rated highest voltage for equipment (1m)
The values of Urn of a bushing shall be chosen from the values of the highest voltage for
equipment, defined in IEC 60038 as given below, in kilovolts:
3,6 — 7,2 — 12— 17,5—24—36—52 — 72,5 — 100— 123— 145— 170—245 — 300—362—420
— 550 — 800 — 1100 — 1 200 kV.
NOTE For standard three phase systems the rated phase-to-earth voltage is tim! d3.
4.2 Rated current (I,.)
The values of ‘r of a bushing shall be chosen from the values as given below, in amperes:
100— 250—315—400—500—630—800— 1 000— 1 250— 1 600—2000—2 500—3 150— 4 000 — 5 000 — 6 300 — 8 000 — 10 000 — 12 500 — 16 000 — 20 000 — 25 000 — 31 500 — 40 000 A.
The above series of currents are in accordance with the values indicated in IEC 60059.
In the case of transformer bushings with the conductor drawn into the central tube (draw lead), the supplier shall indicate the value of the cross-section, the maximum diameter, the material of the conductor, and the material and thickness of insulation, which correspond to ‘r accordance with 4.8.
Bushings for transformers selected with ‘r not less than 120 % of rated current of the transformer and with maximum temperature and maximum daily mean temperature in accordance with Table 4 are considered to be able to withstand the overload conditions according to IEC 60076-7 without further clarification or tests.BS EN 60137 pdf free download.