[OSM-talk] power=line

[Pierre-André Jacquod]

Ed Loach wrote:
> Hatto wrote:
> 
>> According to the "map features" the tag power=line may be
>> completed by a tag
>> "wires=single|double|triple|quad". I have some doubts about the
>> meaning of
>> "wires" in this case. "Map features" say about the "wires" tag:
>>
>>> Number of wires per power cable. "single" (1), "double" (2),
>> "triple" (3)
>>> or "quad" (4). The number of cables may be specified using
>> power=cables.
>>
>> Obviously "power=cables" is a mistake; it should probably be
>> "cables=[number]".
>>
>> Please could some native speakers tell me whether this
>> interpretation is
>> correct:
>>
>> A "power line" is a set of cables hanging between "power
>> towers"; each cable
>> may consist of one or more wires. Thus a German 110 kV line
>> named "0802"
>> with 6 cables [plus one neutral conductor?], each consisting of
>> a single
>> wire, may be tagged as:
>>
>>   power=line
>>   cables=6
>>   wires=single
>>   ref=0802
>>
>> Because of the scarce documentation of "power=cables" some
>> people started to
>> tag e.g. "wires=6*single". I think this should be changed to
>> cable=6,
>> wires=single. Am I right?
> 
> I think you are correct (assuming you meant cables=6). The photo on
> the Key:power wiki page I would tag as power=line, cables=6,
> wires=double. I don't believe the single cable along the very top of
> the pylons carries power, though stand to be corrected. I believed
> it was for signalling, or earthing, or both - certainly there
> doesn't seem to be any insulator

hello,
you are correct, the top cable is usually "earthed" cable for protection
and glass fiber for information transmission and failure detection. (you
are able to detect where there is distortion on the glass fiber based on
signal changes...)
regards
paj