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LOL! Yes, that's the stuff. I already referred back to this thread in the sub-station thread.

Here's how the site stood this morning. Looks as though the trench has been opened out and deepened:

All finished -- The cutover complete, trenches filled in, the old switchgear removed from the enclosure, and nice shiny new tags on the poles:

Well Paul,
It's cool to see the job all finished.
It has certainly given us something to talk about here.
However, one little point, have I not looked at the photo's properly or have I missed something.
In picture No.8 above it shows the cables lying in the trench.
In the final picture, there are no ground-mounted sectionalisers.
So would that mean that there is some sort of a junction in the ground under where the old S/lisers were?.
Or, were the cables merely laid in there, to be "on-site" but also "out of sight- out of mind" to thieves?.
I know it's pretty sad that you should have to spell this out to me Paul, considering that you did give some really good pictures here and still you have to explain it!.
It must be the cold here.

You're actually looking at picture #9..

look at #1, 2, 4, and 8 to see the old switchgear that was replaced..

I'm assuming that the cables seen in the trench go from the new switchgear on the poles, to the existing underground cables formerly fed by the old switchgear, and that there is a splice point where the old switchgear was.

I am also assuming that there are underground circuits fed from this switchgear, otherwise what would be the point of bringing circuits down from the pole in the first place.

That's how I would read it as well. The new sectionalizer with remote-control has just replaced the existing manual switchgear. At no time did I see any trenches dug back to the other poles, so they must have spliced where the old gear was.


Yep, the old cables uncovered in the trench in pic #5 run back under the road.

Two more labels have been attached to the new poles: "Pig unit" on the pole with the air-break switches and "Village" on the pole with the sectionalizer. I'm assuming that the former refers to the farm across the road and that this must be fed from the incoming line. The latter presumably runs down the road to Barton Turf, the village in question.

Despite taking all these photos of the actual work, I haven't really traced the lines running into this arrangement. Next time I'm out that way with a few minutes to spare I'll stop and take a closer look.

O.K., I drove out past this installation again this morning and stopped to examine things more closely. This is purely reasoning (and a little guesswork) on my part, so I could be wrong! If you think my logic is flawed, then feel free to criticize. Here's a map showing the location of the site:



I've added some markings to the first photo to make the description easier to follow.

The house you can see in the background and the trees and bushes either side of it are along the main highway. Just to the left of the photo is the little back lane,

The red arrow marks the path of the underground cables you can see in pics #5 and #9, which run back under the lane.
As you should be able to make out in the photo, there are HV lines from pole C to the lower set of insulators on pole E. These are connected via air-break switches to the upper lines on the pole. From the upper set of insulators are lines running to pole D. Thus the lines on poles C, D, and E are all connected together.

There is a triad of red HV cables running down pole D (by way of some more switches) and disappearing into the ground. No other underground connections run on poles C or E (except for a ground lead for the LV side of the pole-mount xfmr).

The lines disappearing to the right from pole E run in the direction of Barton Turf village. As you can see on the map, B/Turf is on a kind of dead-end loop road.

I've not traced the lines all the way, but I'm assuming that these terminate in B/Turf, as there would be nowhere else for them to go with just the Broads (waterways) and marshland beyond. I think therefore, it's reasonable to assume that power is being fed off to the right from pole E.

The new pole A has been labeled "Village," and this is clearly on the load side of the new sectionalizer. It seems reasonable that the cables disappearing into the ground from pole A take the output from the sectionalizer and feed it to pole D, from which it then feeds down to B/Turf village.

As C, D, and E are all linked together, power must also, therefore, being fed off to the left from pole C.

Again, I haven't been able to trace the latter lines, but they run across the fields almost parallel to the main highway, so probably just feed to odd buildings on the highway and the couple of houses and farms on the next little backlane.

If all the above is true, we've accounted for all HV lines except those underground ones. That means, therefore, that these must be the incoming feed to this site. and logically must connect to the new sectionalizer via pole B.

Where this 11kV feed comes from I have no idea, but there are 33kV transmission lines running roughly northwest from Stalham in the general direction of Worstead. There's probably a 33-to-11kV substation somewhere in the vicinity, although I've never come across it. The new pole B is labeled "Pig Unit," so maybe its somewhere next to the farm. Or does "Pig" refer to something else?

Anyway, as I figure it, power is coming in underground, and going up pole B to the new sectionalizer. From pole A it's connected via underground cxbles to pole D, via air-break switches, on to pole E. The lines from E feed down to B/Turf village, and the link via more air switches to pole C then feeds the other odd buildings back along the main road.

The LV lines from the xfmr provide 3-phase power to the farm off to the left, and two phases are run back a couple of hundred yards to the houses near the main highway.

There are a few unanswered questions in my mind though.

For a start, on the back of pole E is an abandoned cable, hacked off where it emerges from the protective cover and looking as though it's been that way for a good few years. Was this the original feed to the pole?

If you look at the manual switchgear (pic #2) which has just been removed, the sets of cables look relatively new. So did the underground feed originally go straight to pole E, then at some point the switchgear was installed to be able to isolate the Barton Turf feed?

If so though, why was the original cable abandoned?

Why is pole D there anyway? All it does is provide a transition from pole E to the underground feeder. Why didn't they just run the feeder straight up pole E, as was obviously the case at some point in the past?

One further point I noticed today was that the ground from the side of the enclosure round to pole D looks as though it's been dug recently. In fact it's indistinguishable from the newly filled trench from the enclosure to new poles A and B. Maybe they dug this trench, laid a new cable and filled it in without me noticing.

If my logic of the arraangement is correct though, pole D is fed from the load-side of the sectionalizer on pole A. Looking at the pic where the cables were run down the new poles and waiting to be connected, it doesn't look as though there's enough there to have reached all the way round to and up pole D. If you were going to run a new cable up pole D, you run a single length back to pole A, surely? Or if you were going to just splice into the old cables under where the manual switchgear was, why has the ground back to pole D been disturbed?

Ah well.... Just one of those little mysteries, I suppose!


Mike,

The name on the unit is "Whipp & Bourne." Does that mean anything to you?


{ Edited for minor typos }

[This message has been edited by pauluk (edited 06-30-2005).]

Are you sure they aren't setting it up so they can feed it from two different directions?

Paul,
I've just shown your pictures to the Network Operator going off shift, as I take over from him.
The Air-Break Switches that you refer to, are in fact banks of 3 Drop-Out (Expulsion-type) HV fuses.
They are used to protect the lines that they feed and also provide Faults staff with a means of disconnection, should the need arise.
The other NO (Tony, originally from Birmingham, UK), said that your description of the work was good and also that he could not understand why the cable on Pole E was severed like it was.
We made a drawing of this installation on paper and that in itself caused much whining about the way it was drawn.
But, the whole reason for a Sectionaliser in the first place is merely to isolate a certain part (or section) of a power Grid or system, prior to re-energising after either an Earth Fault (caused by maybe a knocked over pole or fallen line) or a Short-Circuit (caused by usually car accidents after the pole gets taken out by a car and the lines fall together).
Putting it simply, it's just like an Electrician making sure that there is no load on a Switch-board, before they turn the Main Switch on. (Of course, after having meggered the installation)
As far as Tony and I could agree, Paul, Pole D is there to maintain a safe distance between the lines, where they change direction and also to allow safe access to the lines should a particular insulator fail.
Paul,
Are you sure that there wasn't a better Earthing system installed, with the upgrade of the work here?.
Paul,
We use Whipp and Bourne Sectionalisers here, they have the patent on the name "Roto-Sect" brand-name.
Just another small point in closing, the Faultsmen here are getting Transcievers installed into our trucks that will allow us to open these units (but not close them)from our trucks, it's linked into LineCAD here.
It still worries me though, what could a software fault do?.

BTW Paul here is a pic of a Pole-top ABS.



The mechanism is operated by a rod system that enables a lever down at about 2.5metres above ground level.
Closing one of these things on to a Fault will end up in a large shower of sparks!!.
That's why we have Sectionalisers.
Minimise the risk.


[This message has been edited by Trumpy (edited 07-01-2005).]