[PRCo] Re: NACHOD SIGNALS--TECHNICAL QUESTION

[Fred Schneider]

Right.  Scott Davis.   Send a note to him care of the museum ... suggest a
stamped return envelope.

Jim Holland wrote:

> Good Morning!
>
> > Fred Schneider wrote:
>
> > Nachod signals count cars in a block.  But for the
> > real answer, send a letter to PTM addressed to the
> > signal guru.  I can see him standing in front of me
> > but I'm terrible with names.
>
>         Scott Davis??
>
>         If 2-opposing cars enter the same section, what happens then?
> Doesn't the system go blank?    While the car using the
> single-track for a reverse move could  *count--out*  the opposing
> car in the single-track, what happens to the  *blank--out*  from
> the opposing move?
>
>         .......AND  how far along was the opposing car  --  did both
> cars enter the single-track at the same identical time, or was
> car  *A*  already beyond the signal when  *B*  made the reverse
> move?
>
> >> rogertrolley.1 at juno.com wrote:
>
> >> I just reviewed an old accident (no location) where
> >> a single track line had 2 miles between sidings.
>
> >> Car entered single track at location A and a car
> >> entered single track at location B at the same time.
>
> >> Car at location B changed ends and returned to
> >> dbl track thru signal trippers of NACHOD system.
>
> >> Question is, did he trip signal to green on outbound
> >> side, even tho there still was a car in the single
> >> track block heading toward location B setting up a
> >> potential head-on collision?????
> >> any takers??    cheers rogertrolley
>
>         This is  *theoretically*  possible unless a  *blank--out*  from
> opposing movements over-rides cancelling the signal.
>
> <><><><><><><><><><><><><><><><><><><><>
>
> Waiting for a bus is as thrilling as fishing,
>     with the similar tantalisation that something,
>         sometime, somehow, will turn up.
>             George Courtauld
>
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>
> James B. Holland
>
> • Holland  Electric  Railway  Operation.......
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>
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