|power = minor_line|
|Lines forming the distribution grid (100-120/220-240 to about 45 kV), usually carried by single poles.|
|Used on these elements|
|Status: de facto|
|Tools for this tag|
Uninsulated power lines carried on poles physically smaller than the high voltage pylons/towers and used for power distribution, are tagged as power=minor_line. Mostly supported on single poles, although sometimes the poles can have several supports, becoming "H-frame" towers, or may use towers when crossing obstacles where sufficient clearance is required. High voltage electricity cables used for bulk transmission are tagged with power=line.
Minor lines may be anything providing power distribution, from interconnected 20,000 volt lines powering a small suburb, to a single cable running from a street lighting pole to the next one. Be careful not to mistake aerial telephone cables (or the like) for power lines.
This tag will apply mostly on the lines that form the distribution grid, which uses voltages between the 100-120 or 220-240 volt utilization voltages and 45,000 volts (45 kV), or the highest known standard distribution voltage used in the country or region. In some areas, distribution may be provided by two primary voltage levels (e.g. 6.6 and 34.5 kV, 11 and 33 kV), with the lower one typically serving smaller customers and the higher one serving larger ones (given their capacities).
A special type of minor lines are overhead feeder lines of transmitters, which can be found at some radio stations working in the VLF/LF/MF/HF-range and interconnect the transmitter building with the antenna. In opposite to the antenna it is not for radiating the signal. Wire antennas are mapped with power=antenna_line.
Bundled and single cable power lines
Lines are usually unbundled, but with the exception of aerial lines using insulated wire and carrying the utilization voltage for the end customers , they may be bundled, but it is rather one whole three-phase circuit (plus neutral) bundled together in order to cross an obstruction (e.g. crossing with a high voltage transmission line), where safety will be a concern if an unbundled line will pass too close, or there is a space constraint to place another cross-arm to an existing pole. In Australia, Aerial Bundled Cable (ABC), where three phase is bundled together and encased, is common in high risk wildfire areas on town fringes and can look similar to telephone cables, although wider. Single Wire Earth Return (SWER) where there is a single wire only, which can be encased, is often used in Australian farming areas and will look identical to telephone cable at a glance.
How to Map
Draw a way following the path of the cables, adding a node at the location of poles or towers. It is not necessary to tag power lines with a layer=* unless two lines cross over each other.
When known, you can also add at least these tags to further define the line:
- voltage=* Nominal voltage (in Volts), for example 20000 or 400
- cables=* Number of the cables carrying currect; Likely values are 1/3/6. Ground wires are not included. Neutral is not usually counted, other than lines connecting to the end customers.
- power=antenna_line for antenna wires spun between multiple support structures
- power=grounding for grounding conductors
- power=line For uninsulated high-voltage power lines, used for bulk transmission.
- power=cable For insulated, underground or sea cables.