BS 6724 : 1997 + A3:2008 specifies requirements for construction and describes methods of test for armoured cables with thermosetting insulation of rated voltages 600/1 000 V and 1 900/3 300 V which, when assessed by the specified tests, produce lower levels of smoke and corrosive products under exposure to fire compared with cables conforming to BS 5467. Cables specified in this standard are intended for use in fixed installations in industrial areas, buildings and similar applications.
In this standard, the level of corrosive (and acid) gases is determined by measurement of hydrochloric acid (HCl) in accordance with BS EN 50267-2-1. The insulation and other components are suitable to permit operation of the cables at a maximum sustained conductor temperature of 90 °C and for a maximum short-circuit conductor temperature of 250 °C.
The cables specified in the standard are all wire armoured and oversheathed, as follows:
a) 600/1 000 V
b) 1 900/3 300 V.
This amendment makes changes to the scope so as to reflect those cable types in common use in the construction and industrial sector. The range of 600/1 000 V cables has been widened by adding 400 mm2 sizes for four-core cables, and four-core cables with reduced neutral and a range of 5-core cables. The range of multicore auxiliary cables has been increased up to 48 core.
BS 6724:1997+A3:2008 supersedes BS 6724:1997+A2:2005, which is withdrawn.
