CPC Size to use?

[trevmai]

Tomorrow i have to install a cpc for a shower circuit. The circuit was disconnected because somebody had removed the cpc. The cables are 10mm single core in trunking - I was just wondering if i would have to install a 10mm cpc in because with 10mm t+e the cpc is not 10mm like the live conductors.

All comments welcome

 

[Spark123]

Table 54G gives the CPC size as the same as the live conductor for core sizes up to 16mm². However if you want to do the adiabatic equation you will probably get away with a smaller size (more than likely as small as 4mm² - you'll need to do the math!). I must admit though, it does sound like a strange setup, singles in trunking for a domestic shower??? Why not just run in a piece of flat twin and earth?