Talk:Tag:power=cable

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Deprecation for underground power lines

Continued from Talk:Proposed_features/Power_transmission_refinement#Difference between cable and line.

Due to some conversations earlier this week dealing with the fact power=cable isn't the best way to describe underground or underwater power lines, I follow the suggestion of User icon 2.svgoligo (on osm, edits, contrib, heatmap, chngset com.) to move the discussion here.

What I propose is to deprecate the current usage of power=cable and use power=line + location=underground (or any proper value) instead. Just like we already do for highways or roads and even pipelines on the water management OSM side. This is all about consistency and vocabulary.

You would find the beginning and some additional explanations there Talk:Proposed_features/Power_transmission_refinement Fanfouer 09:48, 18 January 2013 (UTC)

The highway analogy does not hold: for a common person, a highway looks and works like a highway no matter if it's in a tunnel, or not. Whereas a power line on pylons works and looks totally different when compared to underground cabling; one does not normally even see the underground cables, and they only affect those wanting to dig. There is no process for redefining widely used tags, so using power=line will break lots of things. Alv 10:33, 18 January 2013 (UTC)
I disagree with saying common mappers won't understand. No problem if it properly described on wiki.
Secondly, why underground highway should appear the same for common persons (what is a really common person?) and not an underground power line? Same question for pipelines. Maybe it's because everyone take the highway or pipeline to go on holiday and never power lines. Shame :)
Furthermore, what will be break by deprecating power=cable? There're only 800 ways versus 100k others described by power=line.
Consistency and versatility are the only two things that can ever be justified against particular situations like power=cable. Fanfouer 11:15, 18 January 2013 (UTC)
It's irrelevant whether mappers will or won't understand - I'm sure they do. They don't read the wiki. The 180 000 uses of power=line have described a "big thing on pylons" since 2005, and data consumers expect that, and draw them like that, when they are interested. It's easier for you to consider line and cable as equal, if you are only interested in the functional aspect, than it would be to demand that all other consumers (can you send a message to all of them? who are they?) rewrite their style sheets, possibly their processing tools and many would even require a reimport of the whole planet if the location tag was not included in osm2pgsql style in the past. Alv 10:23, 21 January 2013 (UTC)
So you mean we must freeze current tagging scheme because it exists style sheets and tools already developed... that’s disappointing. Adding tag location=* on power=line will hardly break anything. Rendering defects will only be visible between when people begin using it and renderers get updated. I see it as a minor inconvenience, but I’d like to see it accepted to improve tagging consistency. --Oligo 13:00, 21 January 2013 (UTC)
As I said before, if users want a stable data-set, they can download an extract of planet. Tagging model should be adapted to infrastructure instead of particular use cases. It must aim to the best consistancy and best versatility as for not postpone such problems to tomorrow. Don't procrastinate, if we don't solve the question now, it will come back stronger later. +1 for Oligo. Fanfouer 13:27, 21 January 2013 (UTC)
You should think wider. You consider only good rendering of a general-purpose map for a common user. It is important task. But not a single task! Not less important task is an ability to use the OSM data for a special-purpose maps or special processing. The consistent tagging model will help to solve these tasks an will not ruin a general-purpose maps. Building specialized energetic GISes is one of many possible examples. --Surly 17:44, 21 January 2013 (UTC)
Consistancy and versatility are sufficient things. Deprecating power=cable in favor of power=line will result into uniformity of processing and will be more logical. Electroenergetic facility for power transferring which has full set of phases is tagged with power=line for overground lines. Underground lines are the same things. With "cable=*" tag we represent each particular phase of the line. In case of underground line all the phases of a line are hidden within a single cable shell, so we need not separate each phase -- it's sufficient to tag full set of phases. So power=line with location=underground representing such full set is more appropriate for an underground cable than power=cable. --Surly 12:55, 18 January 2013 (UTC)
According to the wiki, with power=cable, we don't represent each phase of a line. If an undergound cable has 3 phases, you can tag it power=cable + cables=3, the same way you would tag a line with 3 phases power=line + cables=3. Plop76 17:09, 18 January 2013 (UTC)
That's it. Nevertheless, power=cable represent exactly the same functional thing than power=line. As Surly explained so brilliantly, power=line is more logic and versatile than power=cable. That is the quality we must look for. I've gave details about my point of view previously. Fanfouer 17:34, 18 January 2013 (UTC)
with power=cable, we don't represent each phase of a line. — yes, but think about terms. Widely adopting cables=* we have established the term "cable" as a prticular phase of a full line. It'll be logically to use the same term in all the cases where it means the same thing. Underground cable bears full set of phases, not a single one. So why we should think about "cable" as a single phase using it in cables=*, and as a set of phases using it in power=cable? It is illogically! We should use them in a consistent manner. --Surly 17:33, 21 January 2013 (UTC)
I'm not a big fan of the term "cables", i would prefer something like conductors :) Plop76 09:42, 22 January 2013 (UTC)
I think cables=* refers to lives/phases per circuits=* whereas conductor number per circuit is given by wires=*. I agree with you to say "cables" is pretty mistaken and we'd better to write the number of phases.
We must take care of what is intended to be done with power routing system Power_lines#example. Circuits are mapped by relations with ways power=line as a logical layer (all the "per circuit" stuff). It would be a good place to give some relevant logical information about power grids. On ways we should give only physical data without any logical sense (total number of conductors and what else?). The question is to know where the limit between logical and physical is. Fanfouer 13:09, 22 January 2013 (UTC)

Overground location for power cable

The wiki page has recently been updated to remove overground or overhead values from location=* key for power cables.
I think it's a poor idea since high voltage insulated cables are rolled out overhead instead of power lines (uninsulated) between trees or in narrow environments.
Based upon the difference made between cables and lines on OSM, these locations must be restored to maintain the consistency. Fanfouer (talk) 16:43, 19 March 2016 (UTC)

It looks like the removal may have been a good idea. Most of the uses with overhead and overground are really minor lines on power poles which happen to have thin insulation, they are not major transmission lines, according to my check of the data. See the discussion below. --Jeisenbe (talk) 10:50, 13 January 2020 (UTC)

how normal person is supposed to guess whatever given overhead line is power=cable or power=line?

How one is supposed to distinguish coated (not insulated) power wire (power=line), insulated power wire (power=cable apparently according to this page) and uninsulated power wire (power=line) Mateusz Konieczny (talk) 13:48, 22 October 2018 (UTC)

@Mateusz Konieczny: Which power lines do you know that are coated? This seems to be extremely unusual. For insulated power wire some Germans have proposed a new tag.--US Woods (talk) 18:38, 22 October 2018 (UTC)
@US Woods: It is something that I heard about (as part of warning to never get near something that may be downer power wire) - that some are coated and may look like an insulated but are not. Quick googling seems to indicate that it is true - "90% of outside power lines are bare wires and uninsulated. They may have weather coating, but it provides no insulation or protection from electric shock." ( https://www.machinedesign.com/blog/6-dangerous-myths-about-electrical-safety ) Mateusz Konieczny (talk) 09:21, 23 October 2018 (UTC)
A convenient way is to look at ends of wires. A coating will end without additional components since it doesn't provide any insulation and bare wires can often be seen on coating ends. Proper insulation ends are particular and provide safety regarding electricity risks.
Example here, the red cables are insulated and their ends are properly intended to preserve the insulation. Then the overhead part are bare wires Fanfouer (talk) 18:11, 23 October 2018 (UTC)

Again - how one is supposed (during ground survey or when mapping from aerial images) to know whatever given cable is insulated or not? Mateusz Konieczny (talk) 10:11, 26 October 2018 (UTC)

@Mateusz Konieczny: As previously said: When bare copper (or aluminum) wires are visible, it's uninsulated; when you can see a cable sheath made from mostly black plastics, then it's insulated.
Now I get your point: I have never seen a 'weather coating', there is only anti-ice coating, which is still very rare. And the usual superhydrophobic coatings consist of a transparent fluoropolymer, which is unlikely to ever look like a cable sheath.--US Woods (talk) 17:10, 14 January 2019 (UTC)
How can I distinguish "bare copper (or aluminum) wires" from "anti-ice coating" and insulation? During ground survey or when mapping from aerial images? Mateusz Konieczny (talk) 17:30, 27 December 2019 (UTC)
It's only possible with survey imagery and not aerial ones.
  • Bare metallic conductors are often thin and shiny while insulated cables have bigger diameter and matte colours.
  • Bare conductors have to be appropriately spaced according to supported voltage as to prevent any direct contact or electric shock through air.
  • Insulated conductors can be twisted as insulation materials are stronger enough to refrain electric contact.
  • Bare conductors have to be attached with insulators to their supports while insulated cables can be directly bound to poles or terminals. Fanfouer (talk) 23:14, 27 December 2019 (UTC)

Non-powered lines

Should we use this to tag, for example, telephone or cable TV wires? --Floridaeditor (talk) 19:02, 20 December 2019 (UTC)

No this value is only intended for electricity transmission/distribution lines. You may be interested by undocumented telecom=line I guess? Fanfouer (talk) 15:59, 21 December 2019 (UTC)

What is the source of claim that power=line and power=cable is distinguished by whatever it is insulated?

Description in the infobox claims that is "Opposite of uninsulated power=line.". I though that what distinguishes power=line/minor_line and power=cable is that power line/minor_line is overhead while cable is buried. Mateusz Konieczny (talk) 17:36, 27 December 2019 (UTC)

Don't know exactly, infobox description was edited on October 22, 2017.
IEC defintions only consider underground cable (601-03-05) and overhead line (601-03-04) which tend to confirm overhead/underground distinction.
A more general definition of electric line (601-03-03) states that overhead line can consist in insulated conductors.
Nevertheless, for medium and low voltage, overhead cables are often the same as buried ones, we've got location=* to define the location of the line. Using two independant values of power=* is more relevent regarding insulation regardless of location.
The best option we have is still using power=line as defined in 601-03-03 for both uninsulated and insulated systems, underground or overground and use additional keys to state insulation and location. Fanfouer (talk) 23:03, 27 December 2019 (UTC)
I think you are right, Mateusz Konieczny, over 91% of cables are location=underground or location=underwater http://overpass-turbo.eu/s/PHe shows 14909 (mostly location=underground) out of 16382 total with location (https://taginfo.openstreetmap.org/tags/power=cable#combinations), and there are only a few hundred each of location=overhead and location=overground (these two seem to be used synonymously for cables on poles). Of those, 966 location=overhead/overground have a voltage= tag, and 743 are less than 40k which usually means "low-voltage". All are carried by poles, rather than towers and most are short. Most of the high-voltage overground/overhead cables are short connections withing substations or power plants, not transmission or distribution lines. --Jeisenbe (talk) 10:18, 13 January 2020 (UTC)
Beware of not inverting the cause and the consequence here. Overhead lines are often uninsulated because air is commonly enough to ensure safety and operational conditions. Under some special circumstancies, engineers can choose insulated conductors overhead with appropriate supports (insulation is heavier than not insulated) including for transmission. Stating a line for transmission usage doesn't mean it won't be insulated under special circumstancies we're not aware of. That's why I prefer tags that take care of what is seen on ground (insulated or not) instead of what is deducted (transmission or not => never insulated or not). This point is also made for line versus minor_line debate which is another topic. Insulation is not a distribution vs transmission or major vs minor matter even if it's rare for a precise usage. Fanfouer (talk) 11:29, 13 January 2020 (UTC)
Don't forget that most of the mapped power infrastructure is in the transmission voltage range and those will very rarely have insulated cables, unless they are going under ground or in cable canals inside substations. With better quality aerials and/or more open data for power infrastructure this will change. Insulated cables are mostly used for the 110-400V range to consumers, and in some areas for distribution up to 22kV in rural areas with low load. Gazer75 (talk) 09:49, 15 January 2020 (UTC)

Power=line supported by poles

Recent edits aren't completly true : you'll find > 45kV lines supported by poles. It's wrong to write power=line (transmission or not, high voltage or not) is only supported by towers while minor lines can be supported by towers as well. Please adapt your edits to take care of this. Towers vs pole is environmental matter not high-voltage vs low-voltage nor transmission vs distribution Fanfouer (talk) 11:53, 13 January 2020 (UTC)

Are you talking about this page or a different page? You mention "45kV lines" which sounds like power=line instead. --Jeisenbe (talk) 12:22, 13 January 2020 (UTC)
On this page at least mention power=line For high-voltage power lines supported by towers. in see also section could let us understand power=line is always supported by towers which is not true. You'll actually find power=line > 45kV supported by poles Fanfouer (talk) 12:32, 13 January 2020 (UTC)
I didn't add or remove the part about "supported by towers". See https://wiki.openstreetmap.org/w/index.php?title=Tag%3Apower%3Dcable&type=revision&diff=1944267&oldid=1944143 - I only removed "uninsulated." The text in "See Also" previously was "For uninsulated high-voltage power lines supported by towers". My understanding is that >99% of power=line features are connected to towers, and also >99% of power=tower nodes are connected to a power=line, no? --Jeisenbe (talk) 13:45, 13 January 2020 (UTC)
That's right, I mistaken the diff for this page at least. It's more 80/20 rate about high voltage lines and towers/pole supports. To it's important to not propagate the idea that power=line is always supported by power=tower. Supports should be chosen according to their structure, not by the voltage (or the usage, insulation, whatever) they carry. Fanfouer (talk) 17:05, 13 January 2020 (UTC)
If I understand correctly, historically the distinction between power=line and =minor_line was based on the presence of pylons (towers) versus wooden poles. These are obvious differences, while the voltage of the line is harder to find out. I'm sure infrastructure enthusiasts such as yourself have no trouble figuring out the voltage, but anyone can see the tower vs pole distinction from a distince, or even on aerial imagery. Also for rendering it's nice to be able to show power=line earlier, at the same time as power=tower, and show power=minor_line + power=pole at higher zoom levels / smaller scales only. So the idea that voltage is the main determinant seems to be a more recent proposal and not necessarily how the tag is used "de facto". I also am skeptical that there are major transmission lines supported by poles which should be mapped by power=line. Are these poles that are as tall and wide as towers? Usually towers/pylons are used for major transmission lines because they have many wires/cables/conductors and they have to be high above the ground and far apart. I've seen a picture of very large metal "masts" used for this purpose, but these I would still be comfortable mapping as power=tower rather than power=pole, because they are not simple, shorter wooden poles or similar. But maybe this is all off-topic for this page... --Jeisenbe (talk) 01:09, 14 January 2020 (UTC)
Although I'm not really happy with power=line vs power=minor_line, I'm more concerned by power=tower vs power=pole.
this is 90kv transmission line and this is 20kV minor_line. Do you agree these two should be power=pole + material=concrete? Fanfouer (talk) 01:32, 14 January 2020 (UTC)
Sorry, I can't open Google streetview images here. But I put some other examples at https://wiki.openstreetmap.org/wiki/Talk:Tag:power%3Dpole#What_is_the_dividing_characteristic_between_a_power.3Dpole_and_a_power.3Dtower.3F - so maybe that's the best place to continue this conversation. --Jeisenbe (talk) 02:21, 14 January 2020 (UTC)
I suspect that as with any classification (highway=primary vs highway=secondary, highway=track vs highway=path, surface=compacted vs surface=dirt, waterway=stream vs waterway=river etc) there will be objects on the border, plausibly fitting into either one. But it is hard to say here - do you maybe have an image with human or car close to this construction, allowing us to judge its size? BTW, I would argue that you can have power=tower within power=minor_line - I have seen a clear case for a minor power line crossing a large river using standard power=tower. Mateusz Konieczny (talk) 10:46, 15 January 2020 (UTC)

Example of an overhead or overground cable?

The usually meaning of location=overground is a feature which is on the ground or above it, but not high enough to pass under with a truck, lorry or other tall vehicle. Are there, in fact, any power=cable features that qualify for this location type?

A power=cable with location=overhead would be located high above ground, on poles or other supports. But there is no example of this on the page, and many users seem to be misusing this combination for minor distribution lines which have a thin coating over the wires, as found in some countries (parts of the USA, Taiwan, Indonesia, etc). I've read that an underground or undersea power=cable is 15 to 25 cm thick - is this also the thickness we would expect for an overhead heavily insulated cable?

Please link to a good photo of one of these in an overhead location, which can be contrasted with the minor insulated line in this example. --Jeisenbe (talk) 07:55, 15 January 2020 (UTC)

https://goo.gl/maps/F6RwmZYfYcGcCUd66 https://goo.gl/maps/j1es2f1cUjWuFHGW9 are two examples of 22kV lines transitioning to cable. Gazer75 (talk) 09:35, 15 January 2020 (UTC)
Unfortunately we can't use these on the wiki. We need an example with an appropriate license. Also, the examples look just like the photo in Talk:Tag:power=minor_line#ABC_photo which is tagged as a minor line - it's quite low voltage, secondary distribution straight to houses. --Jeisenbe (talk) 13:32, 15 January 2020 (UTC)
Oh I know we can't use them on the wiki as such. I would take pictures myself if I didn't have to spend almost 3 hours to drive 160km to get there. The lines are 22kV distribution, not 230V to homes. Gazer75 (talk) 14:25, 15 January 2020 (UTC)
this one is an overhead cable suspended on wooden poles. It operates at 220V but I may have similar photos for a 20kV overhead cable. These cables are the same overground or underground in France Fanfouer (talk) 18:27, 15 January 2020 (UTC)
Wouldn't this be a power=minor_line? --Jeisenbe (talk) 03:00, 16 January 2020 (UTC)
Back in 2013 or 2014, it has been discussed to move lines, cables, minor_lines to power=line but many rose concerns and this idea was abandoned.
Nevertheless, as we recommend to use location=* to document where a particular cable or line is, I still think it's not a good idea to include location in lines and cables osm definition. Appart from legal or public engineering norms, let's say you first burry a cable underground. A few years later, you come back and remove the dirt which will make the cable overground and not underground any more. It's still a cable, but its location has changed. Then from information management point of view, you'll change location=* value, but not power=* as you didn't changed the actual cable.
I'll go look for such situations (French or Polish opendata) but you can imagine networks where a section of overhead cable goes underground for a few miles without any junction box at the transition. Why should I tag it power=line overhead and power=cable underground if it's the same material installed overhead or underground? Fanfouer (talk) 17:38, 16 January 2020 (UTC)
I woudn't use power=line for the overhead portion unless it was mainily supported on towers. I believe insulated high-voltage cables are usually on poles, so it would be a minor_line, because it looks like a power=minor_line. Openstreetmap is based on what a normal mapper can verify to be true by visiting a place in person, so if it looks like a minor_line, it's a minor_line. We should use other tags for specialist details, like whether it has thick insulation=*, or 1 circuits=* instead of 3, or is used for usage=subtransmission instead of usage=distribution. In contast, "underground" looks different and functionally is much less significant for a general map user. --Jeisenbe (talk) 02:33, 17 January 2020 (UTC)
My point wasn't to distinguish line/minor_line but cables vs whatever lines. In pole talk we observ that lines can be supported by poles or towers independently depending on the environment they go through. I don't see value on defining power=line or power=minor_line according to their support as it's two separate objects. if it looks like a minor_line, it's a minor_line is too binary for misc situations we encounter on ground. What if a line is supported by a mix of poles and towers? If we introduce insulation=* and we already use location=*, then why do we need power=cable actually? Anyone can filter on location=* if they want to get only overhead visible features (overhead as default implied). Fanfouer (talk) 09:53, 17 January 2020 (UTC)
Are you proposing to use power=line for everything then? The last proposal to eliminate power=cable and power=minor_line was not accepted for good reasons, so we are going to continue to have these tags, and the have been defined for many years: a minor_line is on poles instead of towers, a cable is underground or underwater. Certainly there will be border cases that need to be discussed, but we should remember that the great majority of mappers are only going to be adding one tag, based on how the feature looks in real life or an aerial imagery. --Jeisenbe (talk) 12:17, 17 January 2020 (UTC)
Yes I'm a promoter of power=line for everything that carry electricity through a network. Especially against power=minor_line but power=cable if only all properties got their own tags. It's the solution that best match the great majority of mappers are only going to be adding one tag without errors because even we agree on definitions of line, minor_line, cable a certain part of community won't look for details according to you. I still don't get why the community would be not knowledgable to use several tags and understand some simple concepts (made simple with appropriate tags and terminology among other factors) but will choose the best value out of arbitrary 3 that don't describe consistent situations.
The point that large part of community can't handle technical concepts has less meaning to me than the ability and strengh crowdsourcing can have when documentation and editor concepts are consistent (currently effective for line_attachement=*, man_made=monitoring_station, man_made=street_cabinet...) Fanfouer (talk) 12:57, 17 January 2020 (UTC)

I still have not heard of or seen an example with location=overground - that is, above ground but between 0 and 3 meters high, can't travel under. Do these exist, or are they all tagging mistakes for location=overhead? --Jeisenbe (talk) 03:00, 16 January 2020 (UTC)

This is mostly inside substations where there are cable canals. Only instance outside that I can think of would be temporary for construction. Gazer75 (talk) 05:56, 16 January 2020 (UTC)
I'm ok to remove overground from possible locations for lines or cables. Underground, undersea, indoor or overhead are enough. In developped countries is forbidden by law to have overground lines or cables as to allow free and safe movements of goods and people. Fanfouer (talk) 17:38, 16 January 2020 (UTC)
That would prevent proper location tagging of some cables in substations. Gazer75 (talk) 22:32, 16 January 2020 (UTC)
These wiki pages are a compromise between documenting everything that is used (even tags that are rare or contradictory), but also providing a way for new mappers to know the general consensus of the community for mapping a certain feature. So you can certainly use location=overground to map a big cable in a substation which is located at ground level, even if it isn't mentioned on this page, if you don't think power=line or power=minor_line are appropriate. But we don't necessarily have to mention every possible tag combination. If we do keep location=overground, it might be good to suggest "rarely used except within substations and power plants" or similar.
Relatedly, I would also mention on the page that location=overhead is probably only appropriate for high-voltage transmission cables, not the low-voltage 110, 220 or 440V insulated thin cables which are used for secondary distribution, since these are going to be considered a type of minor_line by most mapper who are not experts. And because I have insulated cables which attach my house to the nearest minor_line - these really are not the same thing as a very high voltage transmission cable, from a general mapper and general map user perspective.

Manufacturer name

Hi @Jeisenbe:. Why did you remove provider in the how to map section? Even though manufacturer=* isn't part of recommended tagging, it is still possible to use it to document the company that produce a particular cable. I ask just in case i missed something about this Fanfouer (talk) 17:22, 16 January 2020 (UTC)

Because provider=* is not used with power=cable, according to taginfo, and the other things mentioned are physical characteristics (diameter=*, material=*). It would be fine to mention manufacturer=* if it is commonly used and possible to verify on-the-ground, and I see operator=* is already listed - this is probably what was mentioned by 'provider' i.e. "power service provider" in the USA = operator? --Jeisenbe (talk) 02:09, 17 January 2020 (UTC)