Emergency lighting wiring

[davesparks]

As opposed to banning T&E, IS 201 has changed the requirements for it. This has been in the pipeline for a number of years, with the Amendment to the Wiring Rules being implemented from last Tuesday. What this means is that all sizes of T&E now have an insulated cpc instead of a bare cpc. Also the cpc is of the same cross-sectional area as the live conductors. The use of the old type T&E from the 5th September 2017 has been prohibited.

Any idea why these requirements were brought in? Have there been any incidents which have occurred as a result of uninsulated CPC's or some technical reason for the change?

Do the regulations generally require cpcs to be of the same CSA as the line conductor in all wiring, or is it unique to T&E? Are you permitted to calculate the require s size of CPC if using singles for example?

 

[davesparks]

I despise T&E because it is cheap domestic cable which is widely misused. .

Why do you say that it is domestic cable? Is there any regulatory or technical reason for this?

 

[telectrix]

for small industrial and commercial installations, compare the cost of singles in trunking and galv conduit vs T/E o tray or basket. 9/10 clients will go for T/E.

 

[Risteard]

Any idea why these requirements were brought in? Have there been any incidents which have occurred as a result of uninsulated CPC's or some technical reason for the change?

Do the regulations generally require cpcs to be of the same CSA as the line conductor in all wiring, or is it unique to T&E? Are you permitted to calculate the require s size of CPC if using singles for example?

Yes you can carry out an adiabatic calculation with singles instead of selecting from a table (much like BS7671) - however, it isn't a common approach. I presume that the reason for the full size cpc is largely due to harmonisation.