Re: Flat Wheels in Sydney

["M.B. and C.M.McDonald" <michael.and.colleen.mcdonald@xtra.co.nz>]

But ... what about non-motorised bogies?  Slip (power on)/slide (braking)
ought to be easy enough to detect on motored axles by comparing electrical
signals from each axle.  Come to think of it, shouldn't require too much
additional equipment to detect slide on a non-motorised axle - some
form of sensor which can relay axle speed to a controller.  However,
controlling the braking _on that axle/bogie only_ may be another story!

Cheers
Michael McDonald

David Johnson wrote in message <377CED8B.23044A57@ozemail.com.au>...
>Ron BESDANSKY (formerly Ron BEST) wrote:
>
>> AFAIK, wheel "flats" are due to the wheel locking up during braking, so
that
>> it slides along the rail. Same problem in motor vehicles has been mainly
>> overcome by ABS braking systems - a computer detects that a wheel has
locked
>> up and eases off the braking pressure, then re-applies it. Do any
suburban
>> trains  in Aust. have wheel-slip detection and correction for BRAKING (as
>> opposed to accelerating)?
>
>The tangaras have ABS.  When the computer detects an axle locking up, it
dumps
>the air from the brake cylinder for that axle or bogie.  It doesn't work
very
>well, as the brakes are then re-apply at the same full pressure they were
at
>before and lock up again.
>
>--
>David Johnson
>CityRail Guard
>trainman@ozemail.com.au
>http://www.ozemail.com.au/~trainman/
>
>
>
>