Hi
Whilst checking the wiring into my garage I noticed that the feed into
the garage Consumer Unit is via 3 core armoured SWA cable. The outer
galvanized steel armour terminates at the plastic outer case of the CU
but is not connected to the earth.  The earthling conductor is
connected to the earth bar in the CU as it should be.  Should the outer
steel armour be earthed?
Thanks
Daveo


-- 
daveo

> TN-C earthing is not permitted within a consumer's installation. It is
> permitted on the main supply line to the property, provided the earth is
> separated off into TN-C-S within the supplier's cut out.
>

With concentric the earth and neutral are seperate conductors, the neutral 
strands of the armouring are all seperatly earthed.

The TN-C system is called PEN when used inside an installation (protective 
earth and neutral, TN-C refers to the distribution system).  It is alive and 
well in many of the blocks of flats in the area I work in.  I belive PEN is 
the main system used on the continent and that it is still ok to use in new 
installations, though PME is by far the most popular sytem in the UK.

Regards, Blew


"Christian McArdle"  wrote in message 
news:430ed185$0$13707$ed9e5944@reading.news.pipex.net...

>> It's unusual to see SWA with an earth wire, are you sure it's not
>> concentric.  Consentric carries the earth and the neutral in the
> armouring,
>> with the strands that carry the neutral coated in a PVC sheath.  Typicaly
>> concentric will have no brass glands on each end of the cable.
>
>
> Christian.
>
>