--- In SwissRail@yahoogroups.com, "Krist van Besien"
This morning in Bern. I'm waiting for the 8:02 train to Zürich to
arrive in the station (it's running about 4 minutes late.) On
another track the Zürich - Brig enters the station. This is one
of the recently introduced extra long trains. Composition is
engine - 5 EW IV - 10 IC2000 - engine.
When the train is stopped the pantograph is lowered. Immediatels an
impressive arc forms between the overhead and the panto, and this
arcing continued even with the panto completely lowered (giving us
an arc of more than a meter long!). It only stops when the other
panto, that was raising at about the same time, touches the
overhead. In total the fireworks lasted a second or two.
What happended? I thougth that normally a pantograph would be
isolated before it was lowered. Did the driver make a mistake?
Does such excessive arcing damage the current collector?
At least the arc was to the pantograph and not to the locomotive roof
Did the arc begin while the panto was being lowered or once the arm
was already down?
Isn't the circuit already disconnected before the panto is raised or
Must have been impressive (and shocking) to see.