i’m looking for a complete, correct and unambiguious description
Since its used by many different railroads you may be out of luck for one single definition.
NORAC 2003 : A station designated in the Timetable where signals are remotely controlled from the control station.
GCOR 2010 : A location of absolute signals controlled by a control operator.
The term doesn’t appear in the half dozen or so rule books I looked at that dated 1980 or earlier.
Basically its a place where the signals are manually controlled.
PC used to also use them as a location to tell someone about an issue in that vicinity.
Joe
Hello All,
HERE!?![;)]
I know this won’t help!
Greg;
I believe the term “control point” is used to designate a location where a dispatcher can exercise route options, using manually controlled signals. This may be a passing siding, a junction or simply crossovers between two or more main tracks. The General Code of Operating Rules, effective on UP and SSW on, April 28, 1985, effective on the SP and ATSF on October 28, 1985, as well as the BN, CNW, DRI&NW, LS&I, SOO/MILW, and Minn. Trfr on April 27, 1986 makes no mention of a “control point”. It does explain the definition of, controlled sidings and, controlled signal, as used on a CTC piece of railroad. I don’t ever recall hearing the term control point used on any place but along the east coast. It must be regional usage just like a can of Coke is a “soda” in one state, a “pop” in another, and a “tonic” in another very small region of the country-yes New England, I mean you.
Good luck with that…
All the answers so far are correct.
Generally a series of absolute signals, generally on either side of an interlocking, controlled by a tower operator, dispatcher, or CTC operator.
It is the point of absolute control - do not cross on RED/RED/RED indications.
And yes the term seems to be, or have been, more common on east coast roads.
As an example, my simplified CTC for modeling only uses control point or “absolute” signals and their advance signals. Intermediate permissive automatic block signals are not modeled.
Sheldon
The overall problem with any discussion of signaling and/or CTC is that railroad, region and era effect everything in the discussion.
Not having a government controlled rail system, the US has had hundreds of similar but different signal systems on the hundreds of different railroads.
Applying the same terms to all of them, in every era, simply will not work.
The principles are all the same, the details are almost always different.
And then scaling them down to our models is another problem…
So Greg, once again I would suggest to you that you might get better answers if we knew the reason for your question? You always want to know why? Well I want to to know why you want to know.
Personally, I hate when people ask a leading question that is not the real question or does not contain all the info.
Sheldon
I thought it was a reasonable question.
From this list of railroad definitions, http://jcbd.com/rrterms.html, a controlled point is “A location where signals and/or switches of a traffic control system are operated and/or controlled from a distant location by a train dispatcher.”.
It’s a reasonable question, but all the “qualifiers” make you wonder what the agenda is?
And your link does not seem to work?
Sheldon
Doesn’t work?
Hmmmmm. Looks the same, but try this one:
If this doesn’t work, let me know.
Well, that’s fine, that is pretty much the same as what myself and others said.
But who generated that list? Who are they? Who put them in charge of railroad terms? There is no ownership info on the page?
Sheldon
Oh for goodness sake. Sometimes I think folks are being argumentative just for the sake of being so. It’s a list, it gave a simple definition, and it was concise.
Go bother someone else.
What is a “rivet counter”? [swg]
I’m looking for a complete, correct and unambiguious description. [8D]
And, don’t refer me to that link. It’s not on it. [xx(]
Maxman, I think the original link had a comma included in the link after the .html
What is a rivet counter? Clearly it is the area in a hardware store where the selection of rivets is displayed.
coming to the conclusion that it’s nothing more than a remotely or manually operated device such as a signal or switch.
i’ve been given the impression that it was much more than a signal, a route between signals in a interlocking/signaling system
Primarily in the late 1950s and into the '60s there was a big economic push to eliminate signal towers or interlocking towers and reduce the manhours needed to move trains across the railroad.
Hundreds of manned towers were eliminated, replaced by relay cabinets and remote operated switches. Often they retained the name of the tower i.e. “Conpit” became C.P. Conpit.
Al Perlman on the New York Central was a “progressive” manager and he instituted a massive campaign to install CTC on the NYC and eliminate a gtrat deal of trackage and the associated sitnal towers.
Many of the Control Points are named for the milepost. Near me is C.P. 171 which is 171 miles west of Buffalo.
“Generally” where you find a control point there was once a signal tower there.
History:
https://ekeving.se/ctc/us/NYC_RS_1927.pdf
Throughout this 1927 article you will see the mention of remote control, as in controlled territory, controlled sidings and controlled signals. Thus you can see the extension of calling these specific locations — Control Points.
Regards, Ed
That’s the point Greg, on some railroads, in some eras, it would be each end of a large complex interlocking.
And in other situations it may just be each end of a dispatcher controlled siding on a single track line in the middle of no where.
Signaling is not an absolute science, and again, back in the day each railroad designed and built what worked for them.
I studied signaling for years before deciding how to model it. I studied the prototype, and I studied what others had done over many decades in the model world to simulate it.
My suggestion to anyone in this hobby interested in signaling a layout is to simplify whatever prototype they want to follow because our model situations simply do not lend themselves to the complexities of the prototype - even on the largest club layouts.
Our distances are too short, and most of our operators are not really interested in learning a complex system.
And not that many viewers will ever know the difference.
So why not make it practical in guiding operators, and interesting to viewers, and leave it at that?
On my layout, there are never more than two signal blocks between interlockings, and in many cases only one. All interlockings are “control points”, although I don’t really bother with that term. I simply use the terms “interlocking” and “signal block”. All CTC trackage is one or the other.
The CTC dispatcher sets routes (turnout positions thru interlockings) and then gives authority (clear signal) - I use pushbuttons, not levers, and one or at most two buttons typically align all turnouts for a rout
A “controlled point” is generally an interlocking that is operated from somewhere else.
It might even be nothing more than a signal controlled remotely by the dispatcher (even though there are no switches associated with it).
A CP generally isn’t going to have “manually operated” switches – how would the dispatcher or operator throw them from a remote location?
Now and then, you WILL find a manual switch within the limits of an interlocking, but it will be thrown by the members of a train crew, after receiving permission (or “the unlock”) from the dispatcher or operator.
Examples of controlled points might be CP 72 and CP 75 on the Metro-North Hudson line, south and north of Poughkeepsie.
An example of a controlled signal would be found north of Hudson station on the Hudson line, governing southward movements. I can’t remember if they actually made this “CP 115” or not, it’s been too long since I was there.
I recall a manually-operated switch in the middle of CP 89 (just north of Rhinecliff) on the Hudson line, that once connected to the old CNE. Again, it’s been a long time, 30 years since I worked up that way.
Nope, they are used all over the country. The UP and BNSF have hundreds, if not thousands of them. And the majority weren’t interlocking towers previously either, some were but there are way more that were created when the lines were CTC’d. The term CP really took off when the NORAC and CGOR rule books were written.