What are the advantages and disadvantages of overhead cables?
Relative immunity to short circuits caused by external forces (wind, fallen branches), unless they abrade the insulation.
Can stand in close proximity to trees/buildings and will not generate sparks if touched.
Little to no tree trimming necessary
Simpler installation, as crossbars and insulators are not required.
Ease of erection and stringing, less labor intensive, less construction resources needed.
More aesthetically appealing.
Can be installed in a narrower right-of-way.
At junction poles, insulating bridging wires are needed to connect non-insulated wires at either side. ABC can dispense with one of these splices.
Less risk of a neutral-only break from tree or vehicle damage, increasing safety with TNC-s systems.Significantly improved safety for linespersons, particularly when working on live conductors.
Electricity theft is made harder, and more obvious to detect.
Less required maintenance and necessary inspections of lines.
Improved reliability in comparison with both bare conductor overhead systems and underground systems. Insulated conductors prevent accidental contact and supply can be maintained temporarily in the event of a suspension system collapse.
Additional cost for the cable itself.
Insulation degrades due to sun exposure, though the critical insulation between the wires is somewhat shielded from the sun.
Shorter spans and more poles due to increased weight.
Can lead to much longer repair times for installations in hilly areas due to much higher line weights requiring bigger and more specialized equipment to repair.
Older installations are known to cause fires in areas where falling large trees or branches regularly cause breaks in lines and or in insulation leading to short circuits which can then lead to burning insulation dripping to ground and starting ground fires.
Failure modes through punctures, electrical tracking, and erosion.