Can we use the armour of an SWA as the CPC???

[MDJ]

Not quite sure what your trying to say Fella, I am basically agreeing with engineer but pointing out I never meant to suggest the sheath and third core should be considered as the overall conductor size, just stating the third core is probably adequate but it will inevitably be connected with the shealth at an earth point somewhere in the circuit.

 

[Engineer54]

ARMOUR FOR EARTH OF COURSE THATS WHAT ITS THERE FOR(and underground protection etc) IF TERMINATED TO THE CONTAINMENT (trunking) and that should be earthed anyway then you have just made the armour part of the earthing system common practice to run separate earth along with armour , if actually seen this done with a 5 core armour which gives a 3rd earth overkill maybe but the earth is the most important. ever heard the saying "ITS JUST AN EARTH" without a earth it shouldn't be connected

Only for those that know no different, ...only where the SWA CSA doesn't meet compliance, or where the distance starts to have an effect on the steel wire armour CPC. If your using a 3rd core as your CPC, then it will probably be the same size as the circuit conductors, so will probably already be over kill.

In other words under most circumstances, the armour of SWA cables upto 95mm will always comply as a sufficient CPC means...

 

[Dan]

Just bumping some threads in the Electrical Wiring Theories and Regulations forum category here on our Electricians Forums. If this specific topic isn't current, just ignore it, it'll drop off the list in no time. However, if it's something you'd like to contribute to, feel free to reply and bring it back into current discussion.