There is probably some sort of telemetry box on the roof - I would guess
monitoring voltage and/or current. And the little solar panel keeps the
loggers' battery charged so no one has to get up there and change the
batteries and by not actually deriving power from the line, the design of
the device can be much simpler. It's probably an 'of the shelf' device with
a 'voltage divider' on the front end to step down the 600v.
On Sat, 17 Jul 2021 at 20:58, Andrew C andrewhighriser@...> wrote:
> At the base of the pantograph on one side is a single of what looks to be
> a solar panel. On the other side of the pantograph is a pair of panels.
> They look far from new and perhaps there is a connection to 3506
> advertising BP Solar Panels in 2008. One tram knowledgeable friend thinks
> not. Thoughts?