BS EN 50525-3-21:2011 pdf free
BS EN 50525-3-21:2011 pdf free.Electric cables – Low voltage energy cables of rated voltages up to and including 450/750 V (Ug/U) Part 3-21: Cables with special fire performance – Flexible cables with halogen-free crosslinked insulation, and low emission of smoke.
EN 50525-3-21 applies to flexible cables, insulated and sheathed with halogen-free crosslinked compound and having low emission of smoke and corrosive gases when exposed to fire.
NOTE I Low omission of smoke is checked In accordance with EN 61034-2. Low emission of corrosive gases is checked as pail of the check for absence of halogens (see Annex B of EN 50525-1).
The cables are of rated voltage LID/U 450/750 V.
The cables are intended for the connection of equipment and machinery to the fixed supply.
The maximum conductor operating temperature for each of the cables in this standard is 90 °C.
NOTE 2 HD 516 contains extensive guidance on the safe use of cables in this standard.
This EN 50525-3-2 1 should be read in conjunction with EN 50525-1. which specifies general requirements.
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.
3 Terms and definitions
For the purposes of this document the terms and definitions given in Clause 3 of EN 50525-1 apply.
4 Heat resistant cables (90 °C)
4.1 Heavy duty cables – H07ZZ-F
4.1.1 Construction
4.1.1.1 Conductor
The conductor shall be class 5, according to EN 60228.
4.1.1.3 Insulation
The insulation shall be a cross-linked compound, Type El 8 to EN 50363-5, applied around
each conductor.
4.1.1.4 Assembly
The cores of cables having two to five cores shall be twisted together.
NOTE 1 A centre filler may be used,
NOTE 2 A tape may be apphed around the core assembly before application of the sheath.
4.1.1.5 Sheath
The cores shall be covered with a sheath.
a) For cables with a specified sheath thickness up to and including 2.4 mm:
1) sheath in a single layer, cross-linked compound of type EM 8 to EN 50363-6.
b) For cables with a specified sheath thickness greater than 2,4 mm:
1) sheath either In a single layer, cross-linked compound of type EM 8 to EN 50363-6;
2) or in two layers, with the inner layer made of one of the cross-linked compounds type EM 8 or EM 10 to EN 50363-6 and the outer layer of the cross-linked compound type EM 8 to EN 50363-6.
The sheath applied in a single layer or the inner layer of the sheath in two layers shall, for cables with two to five cores, fill the spaces between the cores. Where a tape of suitable material is applied around the core assembly (see NOTE 2 to 4.1.1.4) this requirement shall not apply, provided that the finished cables shall not have any substantial cavity in the outer interstices between the cores.
4.1.1.6 Marking
The cable shall be marked with the CENELEC code HO7ZZ-F. The marking shall comply with Clause 6 of EN 50525-1.
4.1.2 Requirements
Each cable shall comply with the appropriate requirements given in EN 50525-1. and the particular requirements of this Part.
Testing shall be in accordance with Annex A.
The dimensions of the cables shall conform to Table B.1 for the relevant size.
The requirements to be met for the compatibility test shall be as given in Annex C.
When tested in accordance with the method and procedure given in EN 61034-2, all sizes of cable shall exceed 60 % light transmittance throughout the test.
4.2 Heavy duty multicore cables — HO7ZZ-F
4.2.1 Construction
4.2.1.1 Conductor
The conductor shall be class 5. according to EN 60228.BS EN 50525-3-21 pdf free download.
