View Single Post
  #15   Report Post  
Old June 12th 09, 03:58 PM posted to uk.transport.london,uk.railway
D7666 D7666 is offline
external usenet poster
 
First recorded activity at LondonBanter: Jul 2003
Posts: 529
Default New Electrostar problems

On Jun 12, 2:02*pm, Darth Sunil wrote:
On Jun 10, 7:09*pm, wrote:





On Jun 10, 6:22*pm, "Paul Scott"
wrote:


Axle bearing faults apparently,
Seems bearings was a duff rumour
No ... axle bearings are the traction return earth path. Think about
it ... there is no other point of contact for the earth path.
Ah I see. So where does brush gear come into it? I thought that would be
used to bypass the bearings to avoid heating effects. Might be thinking of
something else though...


Actually I wrote that so fast I am in error ... bearings by virtue of
being metal are conductors, there is some kind of brush that AFAIK
provides the electrical path to avoid arcing in the roller bearing.
IIMU there is a brush within the bearing housing - maybe thats the
issue.


As I surmised on another forum, I suggest bearings size is the cause,
earth path issues the effect


--
Nick


I saw a 377/5 in FFC colours at West Hampstead yesterday, leading a
Southern liveried 377/2.- Hide quoted text -

- Show quoted text -


At least 3 are reported back in traffic from yesterday.

--
Nick