CPC csa

[marksparky]

Hi folks was wondering if someone could point me in the right direction for minimum size of cpc allowed on a 32amp (rcbo) ring? It looks like 1mm to me with 2.5 live conductors. Any help much appreciated:d

 

[Phase2Phase]

if its a ring circuit it wil be 2.5mm live conductors an 1mm cpc if it is old cable (white sheath with red and black cores) if its new cable (grey sheath with brown and blue cores) it wil be 1.5mm

hope this helps

 

[marksparky]

cheers phase 2 phase! the installation is about 30 year old and the problem i have is i have an extra skt 2 add in nearly every room along wit fire alarm and emergency lightin, so i was going to break into existing ring as the client doesnt want to re-wire all due to cost. so i was thinking of wiring a new ring and labelling the sockets with circuit number for (safer) isolation as there would be 2 circuits supplyin each room, and for the old rings putting them down as a code 4 as they dont meet current regs does anyone know if this acceptable? will local authority accept this? by the way this job is a change of use from domestic to a beauty salon. any input much appreciated.

 

[Graeme Harrold]

Owner might be forced into rewire if the insurance company deems it necessary esp with the nature of the business. Id back up your PIR etc with a letter detailing the recomendations to up grade the installation.

 

[Des 56]

If you are installing then certification for your own work
You could comment on the existing if you chose

If you are supplying a PIR for the existing
The ring circuit with the 2.5/1.0mm cpc would have to be calculated for compliance using the adiabatic equation If it is within maximum permissable it would be satisfactory so,rewiring could be recomended but would probably not be necessary

 

[offshorealex]

check the loading the customer plans to put on the rings. If its a beauty salon chances are there will be a lot of 13 amp type loads and although the cabling etc is all done to regs the 32 amp breaker will be constantl tripping because of the load. Might need to bite the bullet and wire extra rings back to the db.