kc_
Member
On EMUs with more than one pantograph and a 25 kV bus (e.g. 390, 397), does the VCB (vacuum circuit breaker) isolate the pantograph from the bus, or the bus from the transformer? If it's the latter, I guess the APMS (automatic power management system) magnets trip all the VCBs at the same time?
I've noticed that on 397s, at-seat power and aircon continued operating whilst going though the OHNS (overhead neutral section). Is that possible? Surely, they're not running those off the battery? I'd have thought at-seat power was non-essential so shouldn't be a drain on the battery.
I've also noticed the sound of the traction motors kick-in a few seconds earlier than aircon and seat power coming back on 350s. What's likely happening here?
I've noticed that on 397s, at-seat power and aircon continued operating whilst going though the OHNS (overhead neutral section). Is that possible? Surely, they're not running those off the battery? I'd have thought at-seat power was non-essential so shouldn't be a drain on the battery.
I've also noticed the sound of the traction motors kick-in a few seconds earlier than aircon and seat power coming back on 350s. What's likely happening here?
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