Mike's Railroad Crossing Forum

An odd setup for a crossing on a freeway:
http://maps.google.com/maps?hl=en&ie=UT ... 8,,0,-3.16

A traffic light/crossing signal combo in town:
http://maps.google.com/maps?hl=en&ie=UT ... 2,,0,-4.35

http://maps.google.com/maps?hl=en&ie=UT ... .33,,0,1.7

Another odd setup:
http://maps.google.com/maps?hl=en&ie=UT ... 9,,0,-4.56
http://maps.google.com/maps?hl=en&ie=UT ... 81,,0,0.57

The lack of mast lights on most crossings seems to ruin the crossings for me.

why are there 3M traffic lights on the signals in the first link?

illinoistrains wrote:why are there 3M traffic lights on the signals in the first link?

I would imagine those traffic lights go red a little ahead of the crossing signals activating. Probably to help with slowing (and stopping traffic) since legally you cannot run a steady red light.

cabman701 wrote:

illinoistrains wrote:why are there 3M traffic lights on the signals in the first link?

I would imagine those traffic lights go red a little ahead of the crossing signals activating. Probably to help with slowing (and stopping traffic) since legally you cannot run a steady red light.

Looks similiar to one posted in Michigan awhile back. Well, except no SORS signs, median signals... and the fact the median signals were installed on the wrong side of the tracks.

CIC755 wrote:An odd setup for a crossing on a freeway:
http://maps.google.com/maps?hl=en&ie=UT ... 8,,0,-3.16

Legally, a true freeway cannot have cross traffic of any kind; hence the name: FREE way, or a right-of-way that is free of traffic controls like stop signs, traffic lights, at-grade RR crossings, etc. However, there are freeways that become divided highways in areas where cross traffic or railroad crossings are unavoidable.

These are usually older Highways and State Routes, with US 101 here in California a prime example. You'll be cruising along, then a sign informs you "END FREEWAY", and bing-bang-boom you get cross streets, then a sign BEGIN FREEWAY, and you're back up to it again.

That's probably TMI.

At the first crossing, there are a lot of strange things I can't figure out:

1) Why are there 2 sets of lights on the median signals, on both sides of the road? And why is one set of lights set at an angle when the road is fairly straight?

2) Why the heck are the median signals on the WRONG side of the tracks??

3) Why did they use expensive 3M PV traffic lights instead of regular ones? There aren't any other signalized intersections around that would necessitate the use of the PV lenses.

4) Why are there 2 relay cases? The one on the post is apparently for the traffic lights. Surely this is a simple enough circut that it could have been placed in the same cabinet as the signal controller?

Weird stuff! I wonder if this is even a busy track.

Josh wrote:At the first crossing, there are a lot of strange things I can't figure out:

1) Why are there 2 sets of lights on the median signals, on both sides of the road? And why is one set of lights set at an angle when the road is fairly straight?

I think I can answer that one. One set of lights is for the left lane, the other for the right lane.

My guess as to why they are on the wrong side of the tracks... when cars stop for the red traffic light, they will be under the cantilever and won't be able to see the cantilever lights very well. They wanted cars to be able to see that the crossing signals were still activated. A mast signal on the same side of the tracks would not be very visable either, and rear lights on the opposite side of the road would not accomplish much either due to the angle.

Josh wrote: 3) Why did they use expensive 3M PV traffic lights instead of regular ones? There aren't any other signalized intersections around that would necessitate the use of the PV lenses.

They don't look too new, that's for sure. You have to remember, the 3M was the pinnacle of traffic light technology for so many years. Because of that, many departments went with it for dangerous and/or high-speed intersections because its indications were so much clearer and brighter than a standard incandescent traffic signal. 3M didn't just market their signal for skewed intersections but also for 'all traffic signal applications' (per the promotional video).

LEDs are much brighter and FAR less expensive. They have made the 3M signal essentially obsolete for these applications and the McCain PV signal put the 3M to bed for good.

Andrew and Cabman - great insights guys, I think you're both correct. This crossing actually makes sense to me now... for the most part.