Re: energy in UK

On Sun, 20 Apr 2025 02:54:20 -0700, Don Y
<blockedofcourse@foo.invalid> wrote:

On 4/20/2025 1:48 AM, Martin Brown wrote:

Earth is mandatory in UK installations often a local earth copper spike
nailed into ground at the premises and the shield of the underground cable.
My electricity actually comes in as two overhead wires. This is now actually
quite rare in the UK and only happens in rural villages.

>
Each subscriber presents a local earth for THEIR load center.
The "nearest upstream" transformer also ties to earth.
>
But, earth is not required (historically) at all loads.  E.g.,
our stove is a three-wire circuit -- two hots and neutral
(no separate earth).  This because of changes to the Code,
over time -- with older installations being "grandfathered" in.

 
Here anything with external metal parts should be earthed by law. Double
insulated things or with no metal surfaces to touch do not have to be and can
be on two pin plugs. Mains electric razors for instance.

>
Current Code is similar.  But, requiring existing homes -- built to the Code
that was in effect at their time of construction -- to retrofit to come
up to the latest Code is considered intrusive and costly.
>
E.g., the house I grew up in had two wire (neutral and hot) circuits
throughout, using BX cable.  So, none of the outlets had earth
connections available.
>

Most UK ring main sockets *require* an earth pin to be present on the mains
plug to open the mechanical cover over the live and neutral terminals. It was
not always so. Previous round pin plugs you could poke a piece of metal or
screwdriver in there and touch live!

>
Outlets (here), now have similar shutters to prevent entry of "unintended
conductors".  But, again, there is no requirement to retrofit them.
Ditto GFCIs, AFCIs, etc.
>

What happens if a drunk takes down a "power pole" feeding said village?

 
Last time it happened was the coldest day of the year and it was the milk
tanker hit black ice and took down 2 poles and 30' of hedge. There is no way he
was doing 30mph! Engineers had us back on by nightfall.

>
Would he have been financially responsible for the repair (though
likely not the secondary losses)?
>
>

A tree fell up the street from our cabin. It hit the wire in the
street, sent a shock wave down the block, and tore the power line off
the front of our cabin. It lay on the ground, still live.

It cost $400 to fix the mess, mostly carpentry. The local utility took
down the wire first and put it back up after the woodwork was fixed.
That was free.

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