3.10.3.3 Continuity
Mechanical and electrical continuity of conductive enclosures shall be maintained.
Exception: Continuity of conductive enclosures need not be maintained where, in accordance with this Standard, the enclosure is not required to be earthed, e.g. the enclosure contains insulated and sheathed cables only.
5.5.3.2 Wiring systems
(a) Conductive wiring enclosures. Exposed conductive parts of wiring enclosures shall be earthed at the end adjacent to the switchboard or accessory at which the wiring enclosure originates.
There doesn't seem to be an clarification or exception in 5.5.3.2 for sheathed cables?
Maybe there's a clause I'm missing?
Conductive wiring enclosures
Re: Conductive wiring enclosures
always pays to look "up" at the higher-level heading(s).
In this case 5.5.3.2 is par of 5.5.3 "particular methods of earthing".
It's not telling us whether we have to earth the wiring enclosures
- that's covered elsewhere; mostly in 5.4 earthing of equipment.
It's just telling us how to earth them if we have to
In this case 5.5.3.2 is par of 5.5.3 "particular methods of earthing".
It's not telling us whether we have to earth the wiring enclosures
- that's covered elsewhere; mostly in 5.4 earthing of equipment.
It's just telling us how to earth them if we have to
Re: Conductive wiring enclosures
Ok, yes that makes sense.
So is there a clarification somewhere else that the conductive enclosure doesn't need to be earthed if the cables are sheathed?
So is there a clarification somewhere else that the conductive enclosure doesn't need to be earthed if the cables are sheathed?
Re: Conductive wiring enclosures
I suspect nothing that specific. On the other hand, if there's nothing saying "must earth xyz" (eg conductive wiring enclosures); then we don't have to.
There is certainly a rule that says short isolated sections don't need to be earthed.
For the rest, I suspect it's just treated as conductive building materials
But of course, if the wiring enclosure is being used as the PEC for the circuit() it contains, then obviously it has to be earthed.
The point of 3.10.3.3 is (again) how we earth it - at the end nearest origin of cable.
There is certainly a rule that says short isolated sections don't need to be earthed.
For the rest, I suspect it's just treated as conductive building materials
But of course, if the wiring enclosure is being used as the PEC for the circuit() it contains, then obviously it has to be earthed.
The point of 3.10.3.3 is (again) how we earth it - at the end nearest origin of cable.