Western Railroad Discussion > Why the need for SHUNT signs?

I spotted this SHUNT sign yesterday along the BNSF Strong City Subdivision in Enterprise, KS. How does the sign serve train crews? In other words, what does this one-word sign denote?

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This is for MOW forces working on the track. They can apply track shunts, basically a wire between the rails, to keep crossing signals from being activated while they have machines on the rail, or so I have been told. Other roads use different terms.

And to alert machine operators such as ballast regulators and tampers to watch out for and not rip off the crossing signal shunts.

fbe Wrote:
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> This is for MOW forces working on the track. They
> can apply track shunts, basically a wire between
> the rails, to keep crossing signals from being
> activated while they have machines on the rail

Speaking for BNSF, MOW cannot place shunts. Signal Dept. has to.

markgillings Wrote:
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> fbe Wrote:
> --------------------------------------------------
> -----
> > This is for MOW forces working on the track.
> They
> > can apply track shunts, basically a wire
> between
> > the rails, to keep crossing signals from being
> > activated while they have machines on the rail
>
> Speaking for BNSF, MOW cannot place shunts. Signal
> Dept. has to.

Well, there always seems to be a maintainer nearby when the gandies are poking through the ballast with a tamper or scraping the shoulders with a regulator. Even the brooms can be dangerous. The first times the signs went up trackside a trainmaster told me 3 or 4 times it was none of my business what the signs were for since I was in the operating department. He finally relented and gave me a general idea why they were there......

Most of the replies are close to the mark.

The sign denotes where one or more shunts associated with a grade crossing is buried. The sign makes it easier to find the shunt in the dark or when buried in snow. You won't see them at all locations. It's also supposed to tell surfacing and tie gangs to be careful, but they rarely heed that. Broom operators seem to take great pride in ripping out as many signal wires and shunts as possible.

Track gangs can use jumpers to temporarily close a gap in a grade-crossing track circuit, but only in series with one rail (while welding a rail joint, for example). Only the signal department, as Mark said, on BNSF can jumper out or shunt a track across the rails to keep a crossing up while MOW is working on the track.

The shunt sign shown in the photo would appear to be associated with the approach for the grade crossing in the background. But it's hard to tell from the photo whether this crossing is signaled. If so, given the short distance, I would assume this to be 20 mph track speed. If it's not for that crossing, then the approach is longer for another crossing in the distance not discernable from the photo and the track speed would be higher.