Re: Crossing Guard Timing in San Rafael
Author: Shortline Sammie
Date: 01-24-2020 - 15:02
Dr Zarkoff Wrote:
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> > North of the SMART station the timing is
> different because
> the approach of trains (SB) and departure of
> trains (NB) are
> different.
>
> To clarify the term "timing" a little: the
> crossing protection must activate around 20
> seconds before a train reaches a crossing. This is
> a CFR/FRA thing nowadays, although it seems to
> have originated in SoCal when the PE started
> installing wig-wags in the 1920s.
>
> Two or more tracks may be set up to activate one
> set of crossing devices. How train arrivals and
> departures on these tracks affects the duration
> the crossing devices are active is an issue
> separate from "timing".
>
> > There's tons of gridlock generated in the
> process.
>
> True, particularly when there is more than one
> track involved and more than one train approaching
> the crossing.
FRA also requires the gate arms to be horizontal for five (5) seconds before the train enters the crossing which can seem like an eternity at times.
Sammie