ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Republic of Ireland/N Ireland distribution/transmission lines questions

Ireland in particular also doesn't follow European-style cluster development patterns. We tend to like the one off sprawling rural home. Hence we tend to have a lot of single phase spurs off the main 3 phase network.

Hello there again,
Intresting to see comments about single phase spurs being common in UK/Ireland. I have also seen O/H distrubition lines in Spain, and I noticed that hardly any of them where single phase, all I saw where 3-ph another thing I noticed is that many rural transformers seemed to be enclosed in hut type structures with the wires running down into them, I have also seen similar structures in France and Italy-is this common distribution practice on the continent? has anyone else noticed these or have any pics of these? and also noticed that most power poles in spain-even for LV lines
were of steel lattice construction rather than wood does anyone else know why this is? is it due to the Spanish climate? does any other country seem to use steel for distribution poles? Also does anyone know the distrbution/transmission voltages in use for Spain?-It would be intresting to know the voltages of those lines. Also can anyone else provide discribtions/pics of O/H distribution lines in various other countries-I find this pretty facinating-how about the Netherlands? Germany? Greece etc.

Perhaps some of you may be interested in these pictures of pole mounted transformers.

This is an old 5 Kva unit.



And here is a replacement 16 Kva unit.



Most people in Ireland will probably know which side of the border these pictures come from but does everyone else?

Martin.

Edited to correct link.

[This message has been edited by MartinX (edited 01-11-2006).]

Hello
Are these pics from NI and if yes is this equipment 11kV?
Luke

These pictures show an 11KV single phase primary with a 240V secondary (yes I do really mean 240).
And yes they are in NI.

Martin.

[This message has been edited by MartinX (edited 01-11-2006).]

ESB small xformers in the republic of ireland are *VERY* similar to the can-shaped device posted above.

10kV (being phased out) or 20kV.

Here's an old single phase service:





Eircom's rural telephone poles are re-used to carry multicore cables feeding homes en-route thesedays. However, they've really allowed the old wooden telegraph poles (>100 years old) to fall apart. They're simply not maintained as some only serve a few homes telco engineers simply never get to them.




[This message has been edited by djk (edited 01-11-2006).]

We're always interested in stuff like that around here! Welcome to the forum Martin.

Wolfgang,
Yes, to a limited degree. As soon as you get anywhere with a concentration of houses in a village or town you'll find 3-phase transformers with a 4-wire 240/415V distribution network around the settlement (each house tapped for 240V single-phase service).

In more rural areas though, you'll often see single-phase spur lines tapped from the 3-ph 11kV network running for relatively short distance to serve isolated houses. The two single-phase xfmrs in my post above are such examples, each one serving just a couple of houses which stand on their own in the countryside.

This being a mostly rural area, we also have little hamlets which have maybe a dozen or two homes spread out along a lane over a distance of maybe a half mile in what is otherwise a fairly isolated area. Some of these have a single-phase (2-wire) 11kV spur line and a single-phase xfmr which feeds 3-wire 240/480V distribution lines which run through the settlement, again with the houses just tapped for 240V 2-wire service.

Here's an example of the latter (notice the three LV wires and two fuses):


The single-phase HV spur in this example continues a short distance to a xfmr serving another tiny isolated community.


[This message has been edited by pauluk (edited 01-12-2006).]

The 16 kVA unit referred to above is made by a company called Pauwels Trafo in Cavan RoI.
I would expect that the ESB may use some of these.

Several people referred to the US style can transformer, I don't think I have seen a picture posted on this forum before so here is an actual example of a single phase or maybe I should say split-phase service for comparison.



Martin.

Link Edited.

[This message has been edited by MartinX (edited 01-12-2006).]

Now I'm amazed:

Is this a SWER system?

And are those 480V used in sort of an American way also?

Wolfgang

I hope I have not confused anyone but this is an actual installation in the USA. I think it is useful for comparison with what we have in the UK and Ireland.

Now I don't wish to drift away from this specific forum title ('Non-US')too much but briefly I will summarise what many of you probably know.

This US transformer primary is connected across phase and neutral/earth (ground) unlike in UK/Ireland where it would be connected phase to phase. This ground wire will run the whole way back to the source of the top phase wire, It is not SWER (Single Wire Earth Return).
The secondary is 120V - 0 - 120V with 3 wires being supplied to each house making 120V and 240V available in each house.
Any of our US friends could expand on this, I think I have got it fairly correct and there is probably a good link somewhere.

Paul posted a UK transformer above with a 240V - 0 - 240V output but every consumer is connected across 0 - 240V (2 wire) only, I think this is quite an unusual arrangement for the UK though.

Our Australian friends could tell us more about SWER and also 240V - 0 - 240V distribution in remote areas where 480V is used for some distant industrial/agricultural high current applications.

Martin.


[This message has been edited by MartinX (edited 01-12-2006).]