Insulation Sleeving - What's the point?

[Scott]

Hi,

I fitted an IP44 light in my bathroom. Included with the light were two strips of wide, thin black "insulation sleeving". These are supposed to fit over the entire length of the Live and Neutral wires coming into the light fitting. I don't understand what the point of these are, could anybody explain? They don't seem to serve any purpose because the wires are naturally alreay insulated anyway with black/red insulation, and if the sleeving is to prevent water from getting to the terminal where the Live and Neutral wires connect, this would still be possible even with the sleeving.

[Roland Butter]

All those I've met before have been in sealed fittings where heat build up may be a problem. They've been silicone sleeving as a belt and braces in case things get so hot that the PVC on the ordinary lighting cable softens.

[Andrew Gabriel]

Yes, the PVC is only rated up to 70C, and it can get hotter inside a lamp fitting or a lamp holder.

[Scott]

[Scott]

[Gel]

When I worked at Osram we included a length of yellow sleeving in bulkheads, and heat shielding was reason; I think it was PTFE material. E W'salers sell heat shrink sleeving; that may be a substitute?

Scott wrote: