EICR Coding - Armour not glanded

[hightower]

Doing EICR on a HMO, DB feeds a Consumer Unit in each room. The feeds to each consumer unit seem to be SWA however the armour is not visible/accessible at either the consumer unit or the DB - it seems to have been cut out behind the DB which is inaccessible.

The cable is buried in the walls and originally I wasn't happy about this, with it not being RCD protected. Originally I was thinking a C2, but now I've had time to mull it over a bit I'm thinking C3 - why would it be any different to a lighting cable buried in the wall without RCD protection.

Then I eventually realised the sensible thing to do was post here and see what everyone else thought.

 

[Andy78]

It would be a C3, you are right, same as any other cable in a wall less than 50mm deep without RCD protection. If there is not even a gland then it would be safe to assume that no metal containment has been used in the walls for it.

I'm assuming there is a cpc contained within the cable of course.

C3 also for lack of proper mechanical connection (gland)

 

[hightower]

Thanks Andy, you are correct with your assumption of a dedicated core for the CPC.

 

[Ian1981]

If the armour is not earthed at either end then I'd be tempted to go C2 as with using ADS the armour needs to be earthed at least one end preferably the supply end.
If cable is damaged and the armour becomes live it causes a real shock hazard.

 

[hightower]

If the armour is not earthed at either end then I'd be tempted to go C2 as with using ADS the armour needs to be earthed at least one end preferably the supply end.
If cable is damaged and the armour becomes live it causes a real shock hazard.

Yeah, so you're saying an unglanded SWA cable buried is more dangerous that a buried T+E because of that floating SWA.

 

[Andy78]

If the armour is not earthed at either end then I'd be tempted to go C2 as with using ADS the armour needs to be earthed at least one end preferably the supply end.
If cable is damaged and the armour becomes live it causes a real shock hazard.

I thought about that but decided that would come under earthing of exposed conductive parts. It has been said that the SWA is not visible or accessible at either end though.

Not sure now, lol. Anyone else ?

 

[Ian1981]

The armour would be classed as an exposed conductive part and would require connecting to earth especially as ADS is the preferred use of fault protection.
I hear what your saying that it's not glanded but it should be so my thoughts are C2

 

[Ian1981]

Yeah, so you're saying an unglanded SWA cable buried is more dangerous that a buried T+E because of that floating SWA.

Yes it should be glanded as per manufacturers instructions and good working practices anyway.

 

[hightower]

So remedial work isn't even as easy as throwing an RCD on the distribution circuits, it's more serious and needs that armouring to be somehow glanded off?

 

[Ian1981]

So remedial work isn't even as easy as throwing an RCD on the distribution circuits, it's more serious and needs that armouring to be somehow glanded off?

The armour becomes pretty well exposed with a nail through it. The layer of PVC below the armour is bedding,there for mechanical protection against the armour. This does not qualify as class II construction, so as it's buried in the wall I'd say it's potentially dangerous if not connected to earth.

You may also get voltage appearing on the armour through capacitive coupling

 

[Andy78]

But there is no firm evidence it is actually SWA, could be another cable type like Hituff ?

You can't say that buried metal is an exposed conductive part because it may become exposed if someone hits a nail into it. It is either exposed at the time of inspection or it isn't.

 

[Ian1981]

But there is no firm evidence it is actually SWA, could be another cable type like Hituff ?

You can't say that buried metal is an exposed conductive part because it may become exposed if someone hits a nail into it. It is either exposed at the time of inspection or it isn't.

If there is a risk of mechanical damage by penetrating the unearthed armour I'd say it's potentially dangerous.
If it's not swa then no worries.

Just my view on it I would C2 it.
Same as if I'd used steel conduit to mechanically protect cables in a wall if it's not connected to earth it's potentially dangerous if penetrated by nails/screws.
I can't see how it would only be a C3 and left satisfactory on a report.

 

[Andy78]

If there is a risk of mechanical damage by penetrating the unearthed armour I'd say it's potentially dangerous.

Just my view on it I would C2 it.
Same as if I'd used steel conduit to mechanically protect cables in a wall if it's not connected to earth it's potentially dangerous if penetrated by nails/screws.
I can't see how it would only be a C3 and left satisfactory on a report.

Same as you would issue a C3 to a twin and earth cable in a wall. No difference in terms of hazards.

 

[Ian1981]

Same as you would issue a C3 to a twin and earth cable in a wall. No difference in terms of hazards.

Except if the live touched onto the armour you'd have a live voltage floating about undetected

 

[Risteard]

Unquestionably a C2 - basic stuff really as you have an exposed conductive part which isn't earthed.

 

[hightower]

Can't say for certain that it is armour except by previous reports saying it's armour - whether there's any truth in these previous EICRs is another matter, but I'm thinking C2 now to cover my backside. Okay, it may not be SWA, but at the moment all evidence leads me to believe it is.

 

[Risteard]

If you're unsure of cable type then you could use FI.

 

[Ian1981]

If you're unsure of cable type then you could use FI.

Of course it's still then an unsatisfactory outcome

 

[hightower]

Of course it's still then an unsatisfactory outcome

It would be anyway looking at the list on this thing, I just want to cover my backside with the whole thing and not leave any door open for comeback.

 

[Risteard]

Of course it's still then an unsatisfactory outcome

Yes indeed it is - as it should be if it's not known to be safe.