Bob and all,
One point of interest, Rainer. Q-Tron is an electronics company, based
in Calgary, I believe, not the name of a device.
And for the record, Q-Tron (yes they are in Calgary) was just bought/obsorbed or
otherwise taken over by MPI, Motive Power Industries!
Q-tron builds numerous
electronic devices used on CPR, including about 90% of the speedometers
used on the SD-40s when the original mechanical analogue speedos were
replaced, and the Speed Control which controls the speed of the
locomotive when the train is loading with coal.
As well as the Datacord 6000 Event Recorders, which in fact are a 'black box'.
(even RaiLink[oops] uses Q-Tron)
The feature you refer to which increased the hauling capacity of the
locomotive was known as the PTC or Positive Traction Control. This
device replaced some of the Electronic modules used in the -2s and, from
what I understand, monitored the amperage going to each traction motor
and when the electricity was cut back to a particular traction motor to
stop the slipping, the extra electricity was transferred to a motor that
was not slipping.
You will notice that some units have an 'axle generator' and cable on each axle.
Those are the units that have PTC or some form of it. As the axle turns, it
'generates' a pulse/signal that is sent up to the Isolation Amp. From there, the
signal can be used for such things as the speedometer, pace setter, event
recorder, crew alert/RSC, as well as being able to look at all six pulses and
determine when a wheel is slipping!
A locomotive with only one or two axle generators would have the older, more
primitive relay type of wheel slip protection.
--
Drew Toner, Mechanical Supervisor,
Pauline Larocque, Toy Poodles,
mailto:keiko@...
