I believe that it is a lightning arrester, and that even though there is a grounded shield wire at the top of the pole, there is a tendency to flachover onto the lowest placed phase wire, especially if the grounding is not good in the area.
We would be interested in knowing what most utilities use as the fault current level at which they install current limiting fuses on 3-phase pad-mounted transformers (to minimize explosion). We realize that: (1) bayonet expulsion fuses have a 3500 amp limit (so we may use fuses in air or a VFI)...
Concern: Medium voltage rural electric distribution line anchor corrosion control. If we have a wood pole with guy wire connected to the multi-grounded neutral and we want to minimize corrosion at the galvanized anchor, would it make any difference if a ground rod was connected at the same pole...
