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[email protected] · April 21st 16, 10:51 PM posted to uk.transport.london

In article ,
(Christopher Jolly) wrote:

Anyone know why the 95s are prone to do this? Perhaps the cooling
system isn't quite up to the job?

Maybe the smell is the heat from the resistor grids being dissipated
when using rheostatic braking? I don't know if the Northern line can
accept regenerative braking. (i.e sending the energy collected back
to the supply source)

I would suspect the smell is from friction braking when regen/rheo braking
isn't able to be used?

I was on the Northern Line the other day but didn't notice any
peculiar smells, you can definitely tell the 95TS performance has
been upgraded since the introduction of TBTC on the Northern Line.

The Northern Line 95TS use newer AC traction motors and IGBT control
despite being older, whilst the Jubilee Line 96TS use DC traction
motors and GTO control despite being newer - this was because the
design specs. for the JLE Extension were frozen back in the early
'90s before widespread use of AC technology.

Although the 96TS uses GTO controls it still has 3-phase AC traction motors.
IGBT was a later 3-phase drive technology which has replaced GTO in practice
for all subsequent builds but apart from a few class 465s GTO-equipped stock
has retained the earlier system.

--
Colin Rosenstiel