Final CCT's with 2 sizes of T&E fitted

[freedomrun]

If faced with a Domestic Final CCT (Lighting or S/O) and it has 2 sizes of T&E used, lets say a lighting CCT with 1.0mm used on some lights and 1.5mm used on other lights and if Zs & IR all complies - When writing out the Schedule of Test Results, what size Wiring conductor should be noted in column 4? Or should a remark be made in column 15 against this CCT stating that two sizes of cable are in the circuit. My question is really aimed at Lighting CCT's, but i guess two sizes of T&E are also found in S/O final CCT's now and again. Any ideas with regard to completing the Schedule of Test Results in relation to this please? Thanks in advance.

 

[Johno]

Personally, I would probably write 1mm (being the lesser), but I suppose a note wouldn't do no harm.


When I was an apprentice working for a biggish firm (mainly office refurbs), they would often take 4mm from the board to the the first sockets and then 2.5mm to finish off the ring, which made sense (cos of volt drop and Zs), but it wasn't until I left and started filling in the certs that I thought what did they used to put on their certs.

There should be more room on certs!

 

[martysparky]

I understand it quite common for lighting ccts to have the switch drops wired in 1mm2 but the loop in/out in 1.5mm2

 

[andekoch]

i used to do the swith drops in 1.0mm, especially 2 way switching and the loop in 1.5mm (assuming calcs fine) and then put 1.0 on the cert as you need to make sure the circuit is ok for worst case. tend to use 1.5 on all now (except 2 way) to save on stock holding.

 

[telectrix]

i used to do the swith drops in 1.0mm, especially 2 way switching and the loop in 1.5mm (assuming calcs fine) and then put 1.0 on the cert as you need to make sure the circuit is ok for worst case. tend to use 1.5 on all now (except 2 way) to save on stock holding.

same here, but usually 3 core+cpc is in 1.0mm, so strappers are in 1.0mm. if strappers and switch wire are in 1.0, i generally put the loop wiring ( 1.5) on ther cert, as the switching cables carry the load for only one light. also, one advantage of wiring switch drops in 1.0 is easy ID of switch wire when 2nd fixing ( laziness really)