This page covers a specific style of color light signals
signals nicknamed "tri-lights",
so named because of the triangular placement of the lenses. Please read my
disclaimer at the bottom of the page for an editorial on the use of the term
Like other "types" of signals such as semaphores, searchlights, Pennsy
Position Lights (PL's), and B&O Color Position Lights (CPL's), this signal
style is being phased out in many locations in favor of the standard Color Light Signal.
Berea, a suburb of Cleveland OH,
is one of many locations where this has recently happened.
GRS (now Alstom), US&S, and Safetran all make this style of signal.
The picture at the top of the page is from
Havre de Grace MD, on Amtrak's Northeast Corridor, SB as you come off the Susquehanna River bridge,
notice the signal uses LED's! More on that page.
As you can see, "tri-light" signals can display a maximum of three colors,
usually red, yellow, and green, with green on the upper right side, and red at the
bottom. I guess in theory they could have any color lens in them, or reverse
the green and yellow positions. If anyone has pictures of anything other than
a typical R/Y/G arrangement, maybe you could shoot me a picture or two?
When using only one or two aspects, the railroads had two different ways of handling
the situation. One, they could just use the same 3-position head and blank out
the unused position. Or, they could use a two or single aspect housing.
An example of all three of the latter on one signal installation is from Berea OH
(left below). When using a full head and they blank out the unused positions,
they usually keep the positions filled with the normal lens color.
This was the first location I had seen using LED lamps, probably around 2002 or so
(Pierce Junction in Houston was the second location in 2006). I got my first
glimpse of them while riding a MARC commuter train up to Perryville and back.
It is located on Amtrak's North East Corridor, just south of the Susquehanna River
bridge and Perryville MD, and controls interlocking for the 4-to-2 squeeze to go
over the bridge.
SB signals where it goes from 2 tracks to 4.
NB signals where it goes from 4 to 2 tracks for the trip over the Susquehanna.
An approach signal in Harrisburg PA
on the western shore of the Susquehanna, this illustrates the practice
of blanking out unused lamp positions as mentioned way up above.
As best I know, this signal was installed during the Penn Central days.
MP 200 on the NS (ex Pennsy) Mainline between Harrisburg and Pittsburgh. These
signals were put in during the Conrail days, as were most of the tri-light
installations on the Middle Division. Very easy access from US22.
Just north of the station, on the other (north) side of Taylor St, is an interlocking,
where the double tracks that go thru San Diego go into one for their trip northward
towards Los Angles. It looks like yellow is on the right side here, as opposed
to the left side on east coast signals. Many thanks to Andrew for
sending this picture in!
This is NOT my standard disclaimer.
I love trains, and I love signals. I am not an expert, I'm not a rivet counter. This is something I have fun with while trying to help others.
Although these pages shouldn't be a place for personal opinion, I feel compelled to explain something here, which
many signal purists will not like. I have been "attacked", or
called to task on numerous occasions for using the term "tri-light" for this style,
telling me that most signals are tri-lights (because they almost all have three lights), but,
Tri-light in this case refers to the fact that the three lenses are arranged in a triangular fashion.
Others have said I should call this signal a Type G signal, because that is what GRS calls it,
but then, Safetran calls it a type V-20R, and US&S a type TR-5/TP-5. Besides, if I
called it a Type G signal, a diehard signal fan (like the ones telling me I should call it a
type G) could confuse it with a US&S Type G signal, which is B&O CPL. So I will
stick with "tri-light", much to the chagrin of the signal purists.
Now for some malarkey you can skip over unless you want to hear me gripe! :-)
(do you want some cheese to go with that whine?) Having a website for the
educational purposes does put me in the spotlight sometimes, and some people
like Paul (if he is reading this, he knows who he is :-), not just tried to
convince me that I should do something because (to him) it was inaccurate of
just plain out wrong, but he started with name calling and the like because I
wouldn't do what HE wanted. All I can say, is that, as a writer, and
editor, I have the responsibility of being complete. If being complete
means that I have to be technically inaccurate, I will do so, because most
people reading these pages are not die hard professionals that spend their whole
lives dedicated to the design, installation, and maintenance of signal systems.
Even for most of them that do, they understand the need to properly
educate everyone out there who is looking for information. The reader can
then decide for himself what he wants to call something. The other place I
have run into trouble on my 700+ pages is with calling lenses that are a deep
blue in color, cobalt blue. I challenge anyone who has a really, really
strong counter opinion to what I write, to start their own website, and give
away the information for free instead of charging for it as Paul does. Paul knows
who he is, he gave me a bunch of crap over the cobalt blue lenses. If,
after reading all of this disclaimer stuff, you STILL feel compelled to write to
me and complain, don't bother, I won't waste my time by responding and your
email will go into the circular file :-)
Now that all of this hooey is said, you can decide for yourself, is you want to
call these lights: color light signals, tri-light signals, or type G signals.
Whatever you choose, most of us will know what you are talking about.
Now, the standard disclaimer..... I love trains, and I love signals. I am not an
expert. My webpages reflect what I find on the topic of the page. This is
something I have fun with while trying to help others.
Please Note: Since the main focus of my two websites is railroad signals,
the railfan guides are oriented towards the signal fan being able to locate them.
For those of you into the modeling aspect of our hobby, my
indexa page has a list of almost everything railroad oriented
I can think of to provide you with at least a few pictures to help you detail your pike.
If this is a railfan page, every effort has been made to make sure that the information
contained on this map and in this railfan guide is correct. Once in a while,
an error may creep in :-)
My philosophy: Pictures and maps are worth a thousand words, especially for railfanning.
Text descriptions only get you so far, especially if you get lost or
disoriented. Take along good maps.... a GPS is OK to get somewhere, but maps are
still better if you get lost! I belong to AAA, which allows you to get
local maps for free when you visit the local branches. ADC puts out a nice series
of county maps for the Washington DC area, but their state maps do not have the
railroads on them. If you can find em, I like the National Geographic map
book of the U.S..... good, clear, and concise graphics, and they do a really good job
of showing you where tourist type attractions are, although they too lack the
railroads. Other notes about specific areas will show up on that page if known.
Aerial shots were taken from either Google or Bing Maps as noted. Screen captures are made
with Snagit, a Techsmith product... a great tool if you have never used it!
By the way, floobydust is a term I picked up 30-40 years ago from a National
Semiconductor data book, and means miscellaneous and/or other stuff.
Pictures and additional information is always needed if anyone feels inclined to take 'em, send 'em, and share 'em, or if you have something to add or correct.... credit
is always given! Please be NICE!!! Contact info is here
Beware: If used as a source, ANYTHING from Wikipedia must be treated as being possibly inaccurate, wrong, or not true.