Talk:Key:line management

Missing "loop" from old system

There seem to be a missing option with this. Back in the old tagging there was a subtag for split I believe called a loop. Basically a tower where the line loops via cables to a nearby substation. Gazer75 (talk) 17:50, 28 November 2020 (UTC)

It's an actual split according tot he current tagging. Such a loop refers to particular topology of a whole power system (or several power systems) and aren't relevant at the local power supports level. Discussions shown this value shouldn't be part of proposed tagging Fanfouer (talk) 14:28, 29 November 2020 (UTC)

This assumes you can map cables or know where they are going. The description for split do not match what I'm talking about. This is a single line looping, not two or more. Gazer75 (talk) 16:13, 29 November 2020 (UTC)

Do you have a picture or a schematic to tell me more about it please? Fanfouer (talk) 16:48, 29 November 2020 (UTC)

Wish I had one near me to take a picture of. Here is a design drawing for a 132kV steel tower: https://imgur.com/a/hiYSx98 and streetview of dual circuit 132kV loop: [1] In both cases the line loops into the substation via one or two busbars and back out again. Gazer75 (talk) 17:33, 29 November 2020 (UTC)

Thank you, it's clear. Look at the last example of line_management=split to find an equivalent situation. Both cables go underground, follow the same path and get into the same substation nearby Fanfouer (talk) 17:39, 29 November 2020 (UTC)

I guess it makes sense if you consider the origin is the nearby substation... I'm thinking in terms of energy flow which is basically going via a loop to the station. Gazer75 (talk) 17:53, 29 November 2020 (UTC)

Yes it is. line_management=* doesn't consider energy flows at all, only static topology patterns matter Fanfouer (talk) 17:55, 29 November 2020 (UTC)

Suggest adding to or modifying the image for the split option on this page to better reflect this situation as well. Gazer75 (talk) 18:07, 29 November 2020 (UTC)

Finding the most appropriate illustration gave me head ache as you'll often find missing situations in it. The point is to state there is no connection here Fanfouer (talk) 18:18, 29 November 2020 (UTC)

Branch that also transition to cable

What do do when you have a branch|straight where the branch is also a transition? Do you go branch;transition|straight? Gazer75 (talk) 18:30, 29 November 2021 (UTC)

location:transition=yes + line_management=branch|straight sounds correct. Fanfouer (talk) 18:41, 29 November 2021 (UTC)

Branch+cross

How to express this situation?

--------+--------------- circuits=1
        |
        |
        |
---------+-------------- circuits=1
        ||
        ||
        ||
      circuits=2

On the northern tower line_management=branch is applicable, that is clear. On the southern tower branch should be combined with cross however the article says it is not allowed. --Kogutowicz Manó (talk) 10:33, 27 August 2023 (UTC)

You simply use cross|branch to indicate one is passing through and one is a branch. It's just one of the options in the wiki that is not displayed, but the system of tagging is the same. Not sure why wiki says it can't be combined. --Gazer75 (talk) 14:15, 27 August 2023 (UTC)

OK, so did I. --Kogutowicz Manó (talk) 15:04, 27 August 2023 (UTC)

Cross covers two or more circuits coming and heading to different directions (they punctually share a support). Two circuits go to the south over the same power line, so cross isn't valid here.

split|branch would be better, you're in this situation actually. Fanfouer (talk) 17:14, 27 August 2023 (UTC)

Oh not. It seems I could not explain the matter. The two E-W lines above are distinct power lines. Their distance is 100 m or so. We can see two towers where the + chars are. Here is a finer figure of line arrangement on the southern tower: --Kogutowicz Manó (talk) 18:22, 27 August 2023 (UTC)

This looks like a cross|branch to me. The top line branch is connected via bottom tower but not to the line. The bottom tower then also has a branch from the other line. There is no splitting going on at the bottom tower and both branched lines run as two circuits on same towers after this. --Gazer75 (talk) 19:04, 27 August 2023 (UTC)

I went to see this tower in place. 2 circuits coming from the south and only one going on to the north to a different tower is a split.

If you wish to consider a cross between east-west line and circuit going to the north, it needs to be on different levels: (cross)|(branch) or split|branch. cross|branch is impossible anyway, cross can't be combined with another value on the same level.

Note that on this particular tower, line_arrangement=horizontal matches all levels Fanfouer (talk) 21:21, 27 August 2023 (UTC)

I think you'll have to make some examples on the wiki like the ones already there. This whole line management tag is not very clear to me tbh. Especially how to differentiate levels on the tagging. Cross can easily be at the same level depending on tower design and how the lines attach. In some triangle and vertical arrangements the crossing line can weave in between. --Gazer75 (talk) 00:51, 28 August 2023 (UTC)

Oh, thanks. Now I see what I missed. I just wonder how to describe cross on one level and branch on the other? --Kogutowicz Manó (talk) 04:06, 28 August 2023 (UTC)

Just a quick idea for the future: what about scheme line_management=level1:cross;level2:straight|split? Or the same without levelN? --Kogutowicz Manó (talk) 04:26, 28 August 2023 (UTC)

Work will go on on three keys line_attachment=*, line_management=* and line_arrangement=* for complex situations as discussions on the last shown a need to reinforce matrix values. Levels are defined according to tower designs as to make a consistent table. We have the framework, let's now go further on the implementation. Currently we should focus on the simple situations, waiting for a more robust matrix approach. I hope to be at SOTM-EU to discuss that. Fanfouer (talk) 11:00, 28 August 2023 (UTC)