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Dave Liquorice[_2_] Dave Liquorice[_2_] is offline
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Default How much current flows through pylons?

On Sun, 19 Mar 2017 23:37:59 -0000, James Wilkinson Sword wrote:

Even with the regulator our voltage wangs about all over the shop

when
the back up 11 kV is being used. Rises to above 255 at night and

drops
to 225 ish during the day. 240 to 245 is the normal range.


Did you get anywhere with your complaint? I get 241V to 256V, which I
consider very poor since 230V is supposed to be the normal.


They just moved the nominal voltage and tweaked the % +/- to pretty
much maintain the same "legal" range. Nothing if anything actually
changed. New supplies might aim for 230 more than 240.

It's enough to regularly make my UPS put an overvoltage warning light on
and step it down itself.


Its the UPS clicking that normally alerts me to the problem. B-)

When I phoned them, they sent someone out in 30 minutes and sounded
worried on the phone,


History: When we moved in we'd get through incandescant light bulbs
at about 1/month. Then I bought the UPS plugged it in and it went
straight into voltage reduction mode. Got out voltmeter, can't
remember what it was but close or over 253. Called the DNO, and there
was a knock on the door 2 hours later. Agreed my readings, peered at
pole transformer, made appointment for a few days later to adjust the
tappings. They came back adjusted the tapping as low as it would go
and we had something just over 240. Time passed and consumption rate
of incandescant light bulbs noticeably dropped.

yet when the electrician arrived and confirmed my voltage readings, he
said "within legal limits, nothing we can do, although if I was in
charge I'd step it down a level".


Didn't offer a voltage monitor? We've had one of those, twice, when
I've complained about the overnight voltage when the primary
substation is being fed from the 11 kV backup. Last time it happened
(up to 256 for several hours over night) they took quite a bit of
interest in the graphs I can produce from the logged UPS voltage
readings. There was a certain amount of head scratching and going to
look at the regulator and the tweak of the 11 kV feed at Little
Selkeld. Got a call from some one in an office and ened up emailing
daily plots to him.

Of course with the local primary on the main 33 kV feed there isn't a
problem and the voltage is very stable at 240 - 245. The voltage
monitor was in for a few days after the feed switched back and the
follow up call said yes it was high during the 33 kV maintenance
period but there wasn't a lot they could do. I've not been aware of
any over voltage since then, which either means the primary hasn't
been on the back up or it has and they've made some adjustments.

Each time I've reported over voltage they've had a man at the door
within hours. Same with outages and speed of supply restoration,
either by rerouting or repairs. We have been off supply for 36 hours
but there had been an ice storm that brought down the lines in
multiple places and the shock of the lines breaking snapped half a
dozen or so poles. One of which carried one of the air switches in
"our" section so wasn't just a rip the stump out, plant a new pole
and restring the lines. But they worked from dawn to dusk for a
couple to days to replace it.

--
Cheers
Dave.