New Electrostar problems
 

On Jun 10, 3:54*pm, "Paul Scott"
wrote:

Axle bearing faults apparently,


Seems bearings was a duff rumour anyway now...

No ... axle bearings are the traction return earth path. Think about
it ... there is no other point of contact for the earth path.

Putting two and two together, the report of 130 mm bearings on 377/5
compared to all previous 377/x with 120 mm bearings causing something
to come into contact that should not could be an electrical earth
issue.

--
Nick

New Electrostar problems
 

wrote in message
...
On Jun 10, 3:54 pm, "Paul Scott"
wrote:

Axle bearing faults apparently,


Seems bearings was a duff rumour anyway now...

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...

Paul

New Electrostar problems
 

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

New Electrostar problems
 

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.

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