Sujet : Re: energy in UK
De : robin_listas (at) *nospam* es.invalid (Carlos E.R.)
Groupes : sci.electronics.designDate : 20. Apr 2025, 19:42:32
Autres entêtes
Message-ID : <oprfdlxv3n.ln2@Telcontar.valinor>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
User-Agent : Mozilla Thunderbird
On 2025-04-20 05:26, Don Y wrote:
On 4/19/2025 12:41 PM, Carlos E.R. wrote:
This is becoming increasingly common. E.g., most new cars include
an embedded "cell phone" for telematics. Many also offer paid services
atop that medium for "roadside assistance".
>
In Spain we now have a new gadget that will be mandatory soon, the V16 beacon. It replaces the reflective triangles we used to signal a broken or accidented car on the road.
>
It is a lamp on batteries and a magnet that we put on the roof of the car, without needing to exit the car. It emits a relatively high power orange light, and communicates the site of the accident to a centralized site a minute after being powered up. It means it has an internet connection of its own, that will work for 10 years without having to pay again. Some internal SIM.
>
I already had to use it once, I had a puncture.
>
<https://en.wikipedia.org/wiki/V16_warning_beacon_lights>
So, it alerts other traffic to your presence. But, it doesn't fix
your problem, does it? Or, does it summon "roadside assistance"?
It is anonymous, that's an important feature so that people don't get paranoid. But you can register a phone app that talks to it, if you want.
So the authorities get information at somewhere about all active beacons at a given time, and they can dispatch the police to go have a look. There is no promise that they do. But those electronic panels on the roads that tell you "accident ahead" should activate. Also information on car navigators like a TomTom (I did not see it).
I don't know if that emergency room is yet built and active.
If you have to exit the vehicle to check under the hood or
replace a tire, you are still at risk and a potential distraction
("rubber-neckers" -- gawkers)
Certainly. Just my case.
But there have been a bunch of people killed while they were just setting the triangles. The authorities thought that the beacon would help with those.
[PLC won't work as there are too many inductors between the customer
and the utility. And, pole-top relays don't save much as there may
only be 2-4 subscribers on a single transformer.]
>
Electricity meters here use some kind of PLC. At the big transformer (several cubic meters) there is hardware to collect the data from each home and either send by another network, or pass somehow to the high voltage side of the transformer. Surely the transformer is remotely controlled, so the data network is there.
>
Here, there is a "smaller, BIG transformer" between the customer and
the "REALLY big transformer" that serves a street/neighborhood.
E.g., 4 subscribers per transformer is typical, here (as that
transformer would have to serve 400A to its group of subscribers)
>
Getting "across" these to a REALLY big transformer that exists in
more limited quantities is the issue. I think the high side of these
local "smaller, BIG transformers" is ~13KV but it may be as low as ~5KV
(I think you can deliver ~3MVA on a 5KV branch; that should support ~100
households.)
>
AFAIK, we don't have those smaller transformers.
Every two residences (on one side of the street), a transformer is sited
between properties, on the property line (actually, an easement), on
the ground (our utilities are below grade).
I have seen them in Canada. But we don't have them. In my block, we had 4 naked wires on the roof, going from home to home. Now they are no longer naked, they are 4 thick cables in plastic, braided. At the small pole, they bring a connection down for some houses. No rule.
On modern neighbourhoods, they are subterranean.
This transformer feeds the two adjacent residences and the two directly
opposite. The "medium tension" primary feed is daisy-chained via
individual coaxial cables from this transformer to the next one,
two properties removed.
At either end of a branch, the primary feed is optionally connected to
a larger transformer (the size of a volkswagen beetle) which feeds
multiple such circuits.
Having both ends of the branch adjacent to potential sources
means the branch can be powered from either (or both!) end.
In the event of a segment failing, the "downstream" transformers
are no longer powered. The utility will identify the failed
segment (there are "sqwakers" in the transformer enclosures that
allow the technicians to identify where power is present/absent).
The segment will be isolated at both ends (the fault obviously
between these two points) and the farthest downstream end of that
isolated portion of the branch will be fed from that "other end"
via a cable segment that is already in place but has to be connected
to the "last" transformer.
[Each transformer has two primary connections (upstream and downstream)
so the transformers at the (one or two) ends have a single connection]
-- Cheers, Carlos.