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Re: What became of SP 3201 and 3207
Author: Hutch 7.62
Date: 02-25-2012 - 08:22
OPRRMS Wrote:
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> Hutch 7.62 Wrote:
> --------------------------------------------------
> -----
> > So a Locomotive converts to from a parallel
> > electric system to Series when run backward?
>
> No. "Transition" is a sequence of electrical
> steps similar to how an automatic transmission
> shifts gears in your car. As the speed increases,
> Forward Transition occurs. As the speed
> decreases, Backward Transition occurs. By the
> mid-1970's, the SDP's were notorious for having
> Backward Transition problems, which the Mechanical
> Department claimed were related to their use in
> commute service. As the speed decreased and
> Backward Transition should've automatically
> occurred, often the units would just stop loading
> altogether. The only way to *legally* get it to
> load again was to momentarily slap the throttle
> handle into IDLE, then quickly bring it back out
> to whatever position it had been in - you had to
> do this real quickly to prevent a serious slack
> run-in and potential break-in-two when the slack
> ran back out.
WOW! thanks for the info. BTW would you recommend any books on locomotive electrical systems? As a Heavy equipment mechanic I find this kind of stuff interesting.
-------------------------------------------------------
> Hutch 7.62 Wrote:
> --------------------------------------------------
> -----
> > So a Locomotive converts to from a parallel
> > electric system to Series when run backward?
>
> No. "Transition" is a sequence of electrical
> steps similar to how an automatic transmission
> shifts gears in your car. As the speed increases,
> Forward Transition occurs. As the speed
> decreases, Backward Transition occurs. By the
> mid-1970's, the SDP's were notorious for having
> Backward Transition problems, which the Mechanical
> Department claimed were related to their use in
> commute service. As the speed decreased and
> Backward Transition should've automatically
> occurred, often the units would just stop loading
> altogether. The only way to *legally* get it to
> load again was to momentarily slap the throttle
> handle into IDLE, then quickly bring it back out
> to whatever position it had been in - you had to
> do this real quickly to prevent a serious slack
> run-in and potential break-in-two when the slack
> ran back out.
WOW! thanks for the info. BTW would you recommend any books on locomotive electrical systems? As a Heavy equipment mechanic I find this kind of stuff interesting.
