New cables into substation
On 12/10/2020 18:08, Andrew wrote:
On 12/10/2020 16:39, Jack Harry Teesdale wrote:
On 12/10/2020 11:55, Andrew wrote:
On 12/10/2020 11:32, Tricky Dicky wrote:
On Monday, 12 October 2020 at 11:26:10 UTC+1, Jack Harry Teesdale
wrote:
On 12/10/2020 10:13, JohnP wrote:
Looking down a hole - as I do - there are some modifications being
done to
cables at a nearby substation. Some of the old cables are being
extended
with "twisted three" cables rather than the usual three phases in a
circular outer.
Any ideas why?
It's cheaper.
I saw that when they dug a trench through a local garden centre car
park to get to a substation and was intrigued. No idea if it is
plaited already on the drum as I never saw that but it looked too
neat and regular to have been done on site.
Richard
I thought that was the aluminium stuff that is regularly used to replace
the 3-phase copper up on poles ?.
Is each conductor separately protected with a steel outer braid, SWA
fashion, or they just using physical depth plus a concrete cap to
protect it ?.
Many UK utility company distribution cables are aluminium these days.
The cables are usually XLPE (cross linked polymer) insulated with a
layer of aluminium stranded armour for protection.
Some cable types incorporate a copper tape screen layer to provide a
earth fault current return path.
Aluminium armour doesn't seem to provide much protection, surely,
compared to steel armour ?
Aluminium is cheaper and doesn't rust! Even the steel wire armour is
easily penetrated by JCB type diggers, so not really that different.
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