Signals in Midwestern USA

[Storknest]

Someone on a virtual forum asked about signals seen on CP lines in this area that appear to have the ability to display four lights (four heads).
http://forums.auran.com/trainz/showpost ... ostcount=1
A couple of users said the fourth one was for lunar white.
I couldn't find anything on signals with four heads.
I did find CP signal guides, one from 2008 had traditional three lights used (red, yellow, green) but two others from 2005 and 2007 had three heads but five different colors (red, yellow, green, lunar white, black?), the 2007 one had SOO DIVISION on it.
http://www.flickr.com/photos/mark_vogel ... 055069@N20
Does anyone know anything about these signals?
And is there a black signal color? I have heard of red, yellow, green, lunar white, blue and purple.

[Chicagorail1]

There is no "black" signal colour. It is just a signal light not illuminated. Any signal, not illuminated is to be taken as its most restrictive indication. Which is red(stop). So a Green(proceed) over red/red, is the same as a Green over black/black.

General Code Of Operating Rules

5.15 Improperly Displayed Signals
If a signal is improperly displayed, or a signal, flag, or sign is absent from the place it is usually shown, regard the signal as showing the most restrictive indication it can give. However, if a semaphore arm is visible, it will govern.

Promptly report improperly displayed signals or absent fixed signals, flags, or signs to the train dispatcher.

[Storknest]

Thanks for clearing up the black color thing though it now looks odd to me they would even print it in a signal guide.

Here is a link to a post showing pictures of the signal heads.
http://forums.auran.com/trainz/showpost ... stcount=20
So I figure the question here is how do rules for three lights maximum work on signals with 4-5 lights?
I have never seen any guide with more than three lights in a rule.

[soo6617]

The signals that you see are manufactured by Safetran and are designed to show indications that would normally require two separate signal heads. You will see these for Distant and Home signals at Control Points.

[techcntr]

soo6617:

I know these signals started appearing in the Twin Cities area, and continued down the River Sub. How far east do these go?

TIA.

techcntr

[rrboomer]

They go all the way east to Rondout. I believe a flashing red has replaced lunar on signals installed the past couple of years.

[techcntr]

rrboomer,

The "single-head" colorlights go all the way to Rondout? Wasn't sure that practice would continue after I left in 1994.
I thought it made for a neat and inexpensive signal. And with the right "logic", almost any combination of aspects
could be displayed.

I presume the old MILW has been single-track CTC'd all the way to Duplainville (or where?)?

techcntr