I assist my local Power Company with Line work, putting in new lines, disconnecting old lines(all overhead, 11kV,33kV and 66kV),
Does anyone have any questions about how we do our work?.
Your input please-
Hi there Trumpy
66kV wouldnt be standard where you are would it?
cheers Craig
I think Aus/NZ adopted British-standard voltages for lines. Much of our local distribution is also 11 and 33kV. We do have some 66kV lines as well, although they're not all that common in most areas.
I understand that in my region there are still a few miles of old 6.6kV lines, although these haven't been a standard for new work for many years.
Hi guys,
Unfortunately, voltages are getting higher and higher around this part of the country, this is all because of the big boom in Dairy conversions, for lighting, water pumps, electrode-boiler-type water heaters, you name it, they've got it. This is where a large portion of the energy used in the South Island, goes to. Dairy farms are getting bigger and bigger, with a 1000 cow farm, being a small one.
Power authorities are hoping that this will
bottom out soon, the rush to upgrade already overloaded lines(running at 33kV),up to 66kV.
Just as a note, we normally only use 11kV out in rural areas for the smallest farmlets
(lifestyle blocks).
Same in this part of rural England: There are 33kV feeders coming into the area about 6 miles away, then all the local distribution is 11kV. By the way, our long-distance transmission lines are 132, 275 and 400kV. Got to go quite a distance from my location to see any of those!) Are these also standard transmission levels in NZ?
Paul,
Those are strange phase voltages to be using?, our long-distance lines are normally run at 110kV, 220kV , the exception to these voltages, is what we call down here, the DC Link, this runs from the Benmore Dam, in Otago, up to the North Island, it runs at 500kV DC, with a whopping great Rectifier Bank at the Benmore end, I've seen it!.
These wires are all overhead, off pylons,the DC link runs as far inland as possible, to keep people away from it, about a year or so ago, a guy tried to cut one of the pylons down, locally, thank God he never succeeded, that would have been an explosion and a half, it is DC, but it's still referenced to earth.
There has been talk of undergrounding the DC
Link, but it has never eventuated.
Just as a short note, every time our power prices increase in the South Island, there are cries to cut the DC Link to the North Island, Old Appy, Take note.
[This message has been edited by Trumpy (edited 11-07-2002).]
Sounds like another Darwin Award candidate for sure!
Is that DC connector the only power link between the North and South Islands of NZ? If so, would I be right in assuming that the 50Hz grids of each island are not synchronized with each other?
I don't know how the U.K. settled on the distribution and transmission voltages that we have. I'm sure the historical aspects of the choice of voltages in different countries would make for interesting reading. I know that much of the French local distribution is now 20kV.
Paul,
As far as I am aware, this is the only power link between our islands, it consists of 8 submarine cables running across Cook Strait, only 4 are used, the others are spares.
In 1996, a trawler, pulled up one of the cables and damaged it beyond repair(they don't bend too well), the company involved was fined NZ$1.5million.
With regard to synchronisation,I think that they actually are, although I cannot be sure.
Ever seen all of the Gear we use on HV lines?.
We've got Hot gloves, Hot sticks, you name it's all Hot!
We have Two totally different techniques over here for working on live lines.
The first is Live Glove And Barrier work,
the other is Hot Stick work.
Power companies want work done with little
disruption to their networks, it's OK, if you don't have to do the work, eh!
Hahaha.. they can cut us loose if they like.
Seriously though, I understand the DC link is only underwater between the islands.
CW
[oops--wrong thread]
[This message has been edited by Bjarney (edited 11-09-2002).]
Craig,
Do you recognise the term "Submarine" as underwater?.
Apparently the DC Link provides an essential power supply for Wellington and a few other places, this makes sure that our over-paid politicians have enough light and heating for their long-haul drinking sessions.
Just wondered if anyone wanted to know how we work on live HV lines,
with Hot Stick work and Live Glove and Barrier work.
Your input Please.
This would be interesting to any Electrical worker.
[This message has been edited by Trumpy (edited 11-14-2002).]
Craig,
How were things up in Auckland during the power failure, a few years ago?.
I was told that a few of the generators
overheated, around town, is this true?
They had a boat at the port as well with Huge cables running from it to the Network
How did they do this?, do you know.
A power failure like that, I would not wish on anyone, it lasted for ages!.
[This message has been edited by Trumpy (edited 11-29-2002).]