BASEC is aware of instances in the market where two different cables are both being marketed as ‘6491B’, when they are very different.
The two types are H07Z-types according to BS EN 50525-3-41 and H07Z1-types according to BS EN 50525-3-31. If these cables are confused and the wrong cable is installed it could lead to serious faults. This warning also extends to distributors and wholesalers to make sure these cables are marketed correctly, and clearly showing their harmonised codes.
Though both cable types are low smoke halogen free, there are two fundamental differences between the cables.
Dr Jeremy Hodge, chief executive at BASEC, explained, ‘Only the H07Z cable type to BS EN 50525-3-41 may be described by the UK cable code 6491B, as set out in the UK annex to the BS EN specification. Although these two cables have similar harmonised codes they have different performance characteristics. For example, if H07Z1 cable were installed in a circuit designed for 90°C operation, the insulation could melt and there could be dangerous faults causing short circuit, overheating, and possibly fire.’