Some Unusual Traffic Signals

Another installment in my occasional series on traffic signals: here is random stuff I’ve discovered around the area.

Is it a Ball or an Arrow?

This intersection of County 81 and Elm Creek Boulevard doesn’t seem to be particularly interesting, but look closer when the light turns green. Then move closer.

The green ball magically changes to an up arrow! 3M, in addition to common balls and arrows and much less common pedestrian lenses, had all kinds of special contraptions for use in their Model 131 programmable visibility signals. One of these was a bimodal indication that would show a ball from a distance and and an arrow up close.

The reason for this is that balls are much easier to see from a distance. Once drivers approach the intersection, however, it changes to an arrow to direct the driver where to go. At County 81 and Elm Creek Blvd., the eastbound and westbound lanes are widely separated by MN 610. What you have is a one way with 70 mph traffic in a place you wouldn’t expect one. Using only left and up arrows reinforces the point that you are absolutely not supposed to turn right.

Like most of 3M’s odd stuff, these bimodal indications are extremely rare. Only one is known to exist in a private collection and only a couple are known to exist on the street. Here’s a video of what you see as you approach, in a car the transition would be much faster.

 

A Danger to Pedestrians

At the same signal, facing the other way is a problem.  Ten points to whoever can instantly see what is wrong with this:

Although this configuration is allowed by the Minnesota MUTCD 4D.4 #2 and #4, (which states that pedestrians may enter against a green arrow when indicated and drivers following an arrow must yield to pedestrians lawfully in the intersection) that doesn’t mean this is a good idea. Most drivers and pedestrians aren’t in the habit of reading obscure sections of the MUTCD or state statutes for exceptions to normal rules, and on the surface this signal is telling both cars and pedestrians simultaneously they have the right of way.

As for fixing it, one option is to just replace it with a standard green ball, and lose the extra feedback the signals provide to keep drivers from turning in the wrong direction. Probably a better option is a flashing yellow arrow right turn signal, that would give a green arrow under normal conditions, and a flashing yellow arrow during a pedestrian phase (this light was installed before this option existed). Although a red ball mated to a flashing yellow arrow is an illegal configuration, state law allows a placement of a sign allowing turns on red arrows after a stop, so that’s what I’d do here.

Since this intersection operates in split phase, there is nothing wrong with the 3M arrows facing north since the west crosswalk will never have a walk while northbound traffic has a green.

Black Signal Heads and Yellow Poles.

Although almost always yellow aluminum signals are on yellow poles, and black poly signals are on galvanized, poles, there are some black poly signals on painted yellow poles. Most of these are where the original signal heads were replaced but not the poles. Below is Fair Oak Avenue at US 10 where the original yellow heads were replaced with black ones on existing poles, likely at the same time as an ADA upgrade project.

Some were installed new like this, for example the interchanges on MN 101 in Otsego. There was a brief period of no more than a year or two in the late 2000s when Mn/DOT had switched from yellow aluminum to black poly signals heads, but had not yet switched from yellow and silver painted to galvanized poles.

Hennepin County, is still using painted poles, but has switched from yellow and silver to all black for new installations. this happened just before their switch from yellow to black signal heads, so a few installations of yellow signals on black poles exist, including the Elm Creek Boulevard and County 81 intersection above. And Minneapolis, which has long used black painted poles and yellow signal heads, has switched to black heads, but still paints the mounting hardware yellow.

Some Black and Silver Poles

For some reason Mn/DOT replaced the lower signal heads here, and while doing it repainted the lower parts black, while leaving the silver masts alone. While I think the yellow and silver poles are ugly even before they start to rust, this looks even worse to me.

 

3M’s Test Intersection

Though long out of the signal business, 3M maintains their own signalized test intersection in Cottage Grove at their “test track”.

 

Some Crouse Hinds Signals

95% of the signals in the area are McCain, 3M, or Eagle brand, with Econolite and Marbelite making up most of the remainder. However here are some rare TCT and Crouse Hinds signals, including the only 8″ versions I’ve seen in the area.  (TCT, or Traffic Control Technologies bought out Crouse-Hinds’ traffic signal business in the early 1980s and used their same molds, the only way to tell is to look at at the tiny  logo towards the top of the back of each section). These are at Vicksburg at 35th Ave, and also Vicksburg Lane at 36th Ave, in Plymouth. Also, note the ICC pedestrian housings, the only ones I’ve seen in the area. ICC was mainly known for their neon pedestrian signals, but I verified on Google Street View that these used to be incandescent. (I don’t believe this area ever used neon, due to the distance from the New York and California manufacturers and they don’t peform well in cold weather.)

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At the US 169 east ramps at North 36th Avenue in New Hope exist some 9″ Crouse-Hinds pedestrian signals with original glass lenses.

 

A Beefy Mast

With wide suburban style roads getting even wider, traffic signal masts have also. There’s a desire to avoid the flimsy poles in the median as these are worth 10 points to Friday night DUIs. It’s not at all uncommon to see a galvanized pole in with black poly signals in one direction, and a painted pole with yellow signals the other, due to the former being a replacement for a knockdown. For a while they were trying to find longer and longer masts, attempting to adopt an 80 foot model, up from the previous maximum of 60 foot, but now they seem to be instead installing substantial, knock-down proof poles in the median.

OOPS!

And finally, I thought I’d show some signal fails (hopefully limited to the type that are of interest to the general public). For want of an unrusted bolt, this this signal failed.

 

More subtly, do you see anything wrong with the black signal on the right?

How about now…

This was a mistake during an entire production run. The companies official line is “China sent us a bad mold but the signals themselves are as usual, the highest quality”. Now that Siemens has spun off its traffic signal head business to Brown Traffic, they plan to replace the Eagle “thunderbird” logo (which somehow never got removed from these during the entire time Siemens owned it), with their new Eagle logo.

Looks like someone is going to lose a game of “3M Jenga”.

Old brittle poly signals + wind