This series of standards is identical with International Electrotechnical Commission standard IEC 60332 Tests on Electric Cables under Fire Conditions — Part 1: Test on a Single Vertical Insulated Wire or Cable (Third edition, 1993), Part 2: Test on a Single Small Vertical Insulated Copper Wire or Cable (First edition, 1989) and Part 3: Tests on Bunched Wires or Cables (Second edition, 1992). It is formulated with a view to meet the needs of the international trade and economic and technical exchanges.
As three parts of IEC 60332 have forewords, they have been merged into an “IEC Foreword” of this series of standards. In addition, Figure 3 of IEC 60332-2 is incorrect and has been corrected in the development of GB/T 18380.2. Secondly, the IEC 60332-3 contains an "Introduction" which, considering that it is instructive for the series of standards, therefore, is equivalent to an introduction to this series of standards. In consideration of the specific situation in China, the fuel used in this series of standards, "propane", is allowed to be replaced by "LPG" with equivalent calorific value.
In order to facilitate the use of GB/T 18380.1 by manufacturers and testing organizations, the clause of IEC 60695-2-4/1 (1991) referenced in Annex B “1 kW nominal test flame apparatus and confirmation of the test flame” to Part 1 of this series of standards is listed separately
For Part 3 of this series of standards, the original IEC publication has Annex A "Proposed Burner", and the burner recommended is a burner made by an American company. As domestic production of burner in accordance with GB/T 18380.2.5 (Figure 4) has been completed, so it is deleted. In addition, in documents 20C/90/CDV to 20C/95/CDV, which convert the original IEC 60332-3 (Technical Report Type 2) to international standards, the clause for determination of oxygen index, namely the original sub-clause 2.9 and Annex B, have been deleted, so it is also deleted from GB/T 18380.3.
GB/T 18380 consists of the following parts, under the general title Tests on Electric Cables under Fire Conditions:
Part 1: Test on a Single Vertical Insulated Wire or Cable
Part 2: Test on a Single Small Vertical Insulated Copper Wire or Cable
Part 3: Tests on Bunched Wires or Cables
This series of standards has been implemented since December 1, 2001. This series of standards cancels and replaces the original GB 12666.2-1990 (Methods DZ-1 and DZ-2) and GB 12666.5-1990 from the implementation date hereof.
This series of standards was proposed by the State Bureau of Mechanical Industry of the People's Republic of China.
This series of standards is under the jurisdiction of National Technical Committee on Electric Wires and Cables of Standardization Administration of China.
IEC Foreword
1. The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2. The formal decisions or agreements of the IEC on technical matters, prepared by technical committees on which all the National Committees having a special interest therein are represented, express, as nearly as possible, an international consensus of opinion on the subjects dealt with.
3. They have the form of recommendations for international use published in the form of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4. In order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparently to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter.
5. The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with one of its standards.
6. Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60332-1 has been prepared by subcommittee 20C: Burning characteristics of electric cables, of IEC technical committee 20: Electric cables.
The third edition of IEC 60332-1 (1993) cancels and replaces the first edition published in 1979 and constitutes a technical revision.
The text of this standard is based on the following documents:
DIS Report on voting
20C(CO)12 20C(CO)15
Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table.
Annex A is for information only.
International Standard IEC 60332-2 (1989) has been prepared by IEC technical committee 20: Electric cables and IEC technical committee 46: cables, wires and waveguide for telecommunication equipment.
The text of this standard is based on the following documents:
Six Months Vote Report on voting
20(CO)175
46(CO)29 20(CO)179
46(CO)39
Technical Report IEC 60332-3 has been prepared by subcommittee 20C: Burning characteristics of electric cables, of IEC technical committee 20: Electric cables.
The second edition of IEC 60332-3 (1992) cancels and replaces the first edition published in 1982 and Amendment 2 (1987).
The text of this standard is based on the following documents:
Six Months Vote Report on voting
20C(CO)e 20C(CO)8
Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table.
A review of this Technical Report will be carried out not later than three years after its publication with the options of: extension for another three years, conversion into an International Standard, or withdrawal.
IEC 60332 consists of the following parts, under the general title Tests on Electric Cables under Fire Conditions:
Part 1: Test on a Single Vertical Insulated Wire or Cable
Part 2: Test on a Single Small Vertical Insulated Copper Wire or Cable
Part 3: Tests on Bunched Wires or Cables
Introduction
Parts 1 and 2 of this series of standards specify methods of test for flame propagation characteristics for a single vertical insulated wire or cable. It cannot be assumed that, because a cable or wire meets the requirements of Parts 1 and 2, a bunch of similar cables or wires will behave in a similar manner. This is because the propagation of flame along a bunch of cables depends on a number of features, such as:
a) the volume of combustible material exposed to the fire and to any flame which may be produced by the combustion of the cables;
b) the geometrical configuration of the cables and their relationship to an enclosure;
c) the temperature at which it is possible to ignite the gases emitted from the cables:
d) the quantity of combustible gas released from the cables for a given temperature rise;
e) the volume of air passing through the cable installation;
f) the construction of the cable, e.g. armoured or unarmoured.
All of the foregoing assume that the cables are able to be ignited when involved in an external fire.
Part 3 of this series of standards gives details of a test where a number of cables are bunched together to form various test sample installations. Three clauses, Clauses 3 to 5, provide details of different test categories having varying volumes of non-metallic material per metre of the test sample subjected to the test.
The method of mounting described as category A, designation F/R in Clause 3 is intended for special cable designs used in particular installations, e.g. power stations.
The method of mounting described as category A, designation ± in Clause 3 is introduced so that a consistent comparison with Clauses 4 and 5 can be made on the effect of increased volume of non-metallic material and test duration.
Tests on Electric Cables under Fire Conditions — Part 1: Test on a Single Vertical Insulated Wire or Cable
1 Scope
This standard specifies a method of test on a single vertical insulated wire or cable under fire conditions and the requirements for compliance.
Notes
1 Since the use of insulated wire or cable which retards flame propagation and complies with the requirement of this standard is not sufficient by itself to prevent propagation of fire under all conditions of installation, it is recommended that wherever the risk of propagation is high, for example in long vertical runs of bunches of cables, special installation precautions should also be taken. It cannot be assumed that because the sample of cable complies with the performance required in this standard a bunch of cables will behave in a similar manner. (See GB/T 18380.3-2001)
2 The method specified is not suitable for the testing of small wires, less than 0,8 mm diameter or small strands less than 0.5 mm2 because the conductor melts before the test is completed. (See GB/T 18380.2-2001)
2 Normative References
The following normative document contains provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the edition indicated was valid. All normative documents are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the normative document indicated below.
IEC 60695-2-4/1:1991 Fire Hazard Testing — Part 2: Test Methods — Section 4 — Sheet 1: 1 kW Nominal Pre-mixed Test Flame and Guidance (idt IEC 60695-4:1993)
3 Sample
The test sample shall be a piece of the finished wire or cable (600 ± 25) mm long.
4 Conditioning
Before testing, all test pieces shall be conditioned at (23 ± 5) °C for not less than 16 h at a relative humidity of (50 ± 20)%.
In the case of insulated wire or cable with a finish of paint or lacquer, this conditioning shall follow an initial period where the test piece shall be kept at a temperature of (60 ± 2) °C for 4 h.
5 Test Apparatus
The test apparatus and arrangement are illustrated in Figures 1 and 2.
The test apparatus shall be contained within a suitable chamber, substantially free from draughts during the test duration, but with facilities for disposing of noxious gases resulting from burning. The chamber shall be maintained at a temperature of (23 ± 10) °C.
Notes
1 If the requirement for the draught-free closed area is met by the use of a standard fume cupboard, it must be capable of independent operator-control of the extractor fan such as to permit operation with the extractor "OFF". Some fume cupboards may not be supplied with this facility.
2 If a fume cupboard is used as the draught-free test area, the following safe operating practice is recommended:
a) turn off extractor fan, seal the outlet;
b) pull down front door of fume cupboard to leave a gap sufficient to manipulate burner into position;
c) ensure operator is protected;
d) do not move the door of the fume cupboard during the test;
e) at the end of the test evacuate the fume cupboard fully before opening the door.
Figure 1 Test apparatus — Metallic screen
Distance A: Minimum length of uncharred surface = 50 mm
Distance B: Maximum length of downward limit of charred surface = 540 mm
Distance C: Length from base of screen to bottom of sample = 50 mm (approximately)
Figure 2 Arrangement of sample in test apparatus
6 Arrangement of Test Piece
The test piece shall be fixed at two positions and aligned vertically within a three-sided metallic screen (1 200 ± 25) mm high, (300 ± 25) mm wide and (450 ± 25) mm deep with open front and closed top and bottom (see Figure 1).
The test piece shall be secured to two horizontal supports by means of 1 mm2 copper wire so that the distance between the bottom of the upper support and the top of the lower support is (550 ± 5) mm. In addition the test piece shall be positioned so that the bottom of the specimen is approximately 50 mm from the base of the screen (see Figure 2).
7 Ignition Source
The ignition source shall be a gas burner complying with IEC 60695-2-4/1 which includes a method of confirmation of the test flame. See Annex B .
Note: IEC 60695-2-4/1 specifically refers to the need to study also IEC 60695-2-4/0.
8 Test Procedure
Safety warning
Precautions shall be taken to safeguard personnel against the following when conducting tests:
a) the risk of fire or explosion;
b) the inhalation of smoke and/or toxic products, particularly when halogenated materials are burned:
c) toxic residues.
Foreword II
IEC Foreword IV
Introduction VI
1 Scope
2 Normative References
3 Sample
4 Conditioning
5 Test Apparatus
6 Arrangement of Test Piece
7 Ignition Source
8 Test Procedure
9 Performance Requirements
Annex A (Informative) Bibliography
Annex B (Normative) 1 kW Nominal Test Flame Apparatus and Confirmation of the Test Flame
