IEC 61034-1:2019 pdf download

IEC 61034-1:2019 pdf download.Measurement of smoke density of cables burning under defined conditions – Part 1: Test apparatus
1 Scope
This part of IEC 61 034 provides details of the test apparatus to be used for measuring smoke emission when electric or optical fibre cables are burnt under defined conditions, for example, a few cables burnt horizontally. The light transmittance (l t ) under flaming combustion and smouldering conditions can be used as a means of comparing different cables or complying with specific requirements. NOTE For the purposes of this standard, the term “electric cable” covers all insulated metallic conductor cables used for the conveyance of energy or signals.
2 Normative references
The following referenced documents are indispensable for the application 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 60695-4, Fire hazard testing – Part 4: Terminology concerning fire tests IEC Guide 1 04:1 997, The preparation of safety publications and the use of basic safety publications and group safety publications ISO/IEC 1 3943:2000, Fire safety – Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions in IEC 60695-4 apply, or if a term is not defined in IEC 60695-4 then the definition in ISO/IEC 1 3943 applies.
4 Details of test enclosure
The equipment shall comprise a cubic enclosure with inside dimensions of 3 000 mm ± 30 mm and constructed of a suitable material fixed on to a steel angle frame. One side shall have a door, with a glass inspection window. Transparent sealed windows (minimum size 1 00 mm × 1 00 mm) shall be provided on two opposite sides to permit the transmission of a beam of light from the horizontal photometric system. The distance from the floor to the centre of these windows shall be 2 1 50 mm ± 1 00 mm (see Figure 1 for plan view). The walls of the enclosure shall include orifices at ground level (i.e. not greater than 1 00 mm above the level of the chamber floor) for the passage of cables, etc., and to permit the enclosure to be at atmospheric pressure. No orifice shall be directly behind the fire source or on the same wall. A minimum of two orifices shall be provided and the total area of the orifices open during the test shall be 50 cm 2 ± 1 0 cm 2 . NOTE 1 Two orifices, each with an area of 25 cm² ± 5 cm², and located on two opposite walls, one under the light source and one under the receiver have been found to be suitable.The ambient temperature outside the enclosure shall be 20 °C ± 1 0 °C and the enclosure shall not be directly exposed to sunlight or extreme climatic changes. NOTE 2 It should normally be possible to extract fumes from the enclosure after each test through a duct complete with valve which should be closed during the test. The duct may include a fan to increase the rate of extraction. It is recommended that the door of the enclosure be opened to assist the extraction process. A draught screen, 1 500 mm ± 50 mm long and 1 000 mm ± 50 mm high, shall be placed in the enclosure, at the position shown in Figure 1 . It shall abut on the back wall (with a maximum gap of 1 0 mm) at a point 750 mm ± 25 mm from the side wall, and shall be curved to intersect the centre line of the enclosure at a point 1 400 mm ± 25 mm from the point of abutment.
5 Photometric system
5.1 The photometric system is illustrated in Figure 2. The light source and the receiver shall be placed opposite each other externally, in the centre of both windows in the two opposite walls of the cube without making physical contact, as shown in Figures 1 and 2. The light beam shall traverse the cube through the glass windows in the side walls.