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What is an Interlocking?

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What is an Interlocking?
Posted by Anonymous on Thursday, December 11, 2003 6:26 PM
Can anyone link me to a diagram or photo if an Interlocking? The material I am reading is not that clear on the concept.
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Posted by mudchicken on Thursday, December 11, 2003 6:47 PM
Interlocking (n): A set of signals and signal appliances connected together so that their movement follow each other in a predetermined successive order. They generally controll interconnected turnouts (switches) or track crossings (diamonds). Also called interlocking plant or simply "the plant" - Simmons Boardman "Dictionary of Railway Track Terms"....

gnenjnj:

An interlocking can be at a crossing diamond (including non-signal "manual interlockings" with link and pin mechanical conections to derails and signs), thru a crossover or thru some sort of approach to a gauntlet structure. All of the old towers at railroads crossing railroads are some form of interlocking. A hump yard where the tower controls the switches is technically an interlocking.

For diagrams, look at Santa Fe (ATSF) historical or Jerry Jordak's Penn Central sites for schematic diagrams of what some interlockings look like.

Mudchicken

ps - Ed, does this make your troops some kinda "logic driven organic all weather terminal interlocking and do it with a smile" appliance? (new Unihead daffynition?)
Mudchicken Nothing is worth taking the risk of losing a life over. Come home tonight in the same condition that you left home this morning in. Safety begins with ME.... cinscocom-west
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Posted by Anonymous on Thursday, December 11, 2003 7:18 PM
broadway.pennsyrr.com/Rail/Prr/Maps/Itlk/ - 8k Here is an extensive list of Pennsy interlockings.Don
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Posted by CSSHEGEWISCH on Friday, December 12, 2003 6:49 AM
Not all towers or junctions are interlocking, Brighton Park is the prime example of a non-interlocked crossing with mandatory stops by all trains required by law.
Interlocking means that all switches and signals controlled by the tower are interlocked in such a way so that conflicting movements by more than one train cannot be allowed.
Interlockings can be manned, remotely controlled or automatic.
The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by edblysard on Friday, December 12, 2003 7:44 AM
They are "self activating mobil logic driven organic all weather terminal interlocking do it with a smile" appliances.
Crap, now we have to come up with uniforms.
Ed

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Posted by mudchicken on Friday, December 12, 2003 10:17 AM
QUOTE: Originally posted by edblysard

They are "self activating mobil logic driven organic all weather terminal interlocking do it with a smile" appliances.
Crap, now we have to come up with uniforms.
Ed



[:D][:D][:D][:D][:D][:D][:D][:D] Outstanding! : rest of the office can't figure out why all the giggling and guffaws down at this end of the hall! Please, never lose that dry sense of humor......mc
Mudchicken Nothing is worth taking the risk of losing a life over. Come home tonight in the same condition that you left home this morning in. Safety begins with ME.... cinscocom-west
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Posted by michaelstevens on Friday, December 12, 2003 10:35 AM
Nice website Mr. "barbarosa" -- never did find the PRR interlockings -- but the warning about the meteorite sure is topical, with today's news.
British Mike in Philly
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Posted by JoeKoh on Friday, December 12, 2003 3:30 PM
I have pics from deshler ohio and can draw you a diagram too.just email me.
stay safe
Joe

Deshler Ohio-crossroads of the B&O Matt eats your fries.YUM! Clinton st viaduct undefeated against too tall trucks!!!(voted to be called the "Clinton St. can opener").

 

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Posted by Anonymous on Friday, December 12, 2003 9:42 PM
Mr "Michaelstevens" I am very sorry that the link i posted in response to your question about interlockings no longer works.I try to find online help for members of this forum who may not have the time to spend online that i do.I am sure you realize that a lot of web pages are put up by people like you and i.These pages can be lost when people change ISP's or simply quit maintaining the site.When i posted my reply the URL i listed worked ,and i posted it in good faith.I would have replied to you in person but you have choosen to hide your identity from the general public of this forum. I hope :sir:That i have caused you no great trouble.Don
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Posted by DSchmitt on Saturday, December 13, 2003 5:03 PM

The page sugested by bararosa works If you have trouble go to this page first

http://broadway.pennsyrr.com/Rail/Prr/

It links to the interlocking page



There is a lot of info about the Pennsylvania Railroad.

Another page that may be of interest is the one on signals

http://broadway.pennsyrr.com/Rail/Signal/



The pages belong to Dr. Mark D. Bej MD

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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Posted by Anonymous on Sunday, December 14, 2003 12:57 PM
I've always wondered that, too.
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Posted by Anonymous on Monday, December 15, 2003 6:49 PM
It points up some of the glamours to mention the towers and crossings but an interlocking can be as simple as the entrance to a siding. Provided of course that a signal protects the clearance points at both facing and trailing ends of the switch, and said siganlling is provided for all possible movements over or through that switch.
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Posted by Anonymous on Monday, December 15, 2003 7:12 PM
I always thought that interlocking was the relationship between your model railway scenery and your wife's jumper and the insuing cursing, "why did you build that thing in here?"
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Posted by Anonymous on Tuesday, December 16, 2003 4:17 PM
The January 2004 issue of Model Railroader magazine has a good article on mechanical interlockings with detailed diagrams showing how they work.
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Posted by edblysard on Tuesday, December 16, 2003 6:48 PM
Interlocking also describes the relationship between my wife's purse and her checkbook, she cant open one with out opening the other!
Ed[:D]

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Posted by dharmon on Tuesday, December 16, 2003 6:52 PM
QUOTE: Originally posted by edblysard

Interlocking also describes the relationship between my wife's purse and her checkbook, she cant open one with out opening the other!
Ed[:D]


GET OUT!.......All this time I thought my wife was at the store.....just to find out she's been leading a double life and she's married to you too!!!!!![:0]
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Posted by edblysard on Tuesday, December 16, 2003 7:49 PM
Tell ya what, she's got the fastest checkbook in the west!!!
She's already melted three pens.
Ed

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Posted by Anonymous on Tuesday, December 16, 2003 8:19 PM
Here is a definition from the general code of railroad rules. INTERLOCKING Signal appliances that are interconnected so that each of their movements follows the other in a proper sequence. Interlockings may be operated manually or automatically. This should clear up the problem. I am a retired Conductorr/Trainman and Yardmaster for the Boston and Maine Railroad. Brian Cummings Ma.
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Posted by Anonymous on Tuesday, December 16, 2003 8:24 PM
Here is a definition from the general code of railroad rules. INTERLOCKING Signal appliances that are interconnected so that each of their movements follows the other in a proper sequence. Interlockings may be operated manually or automatically. This should clear up the problem. I am a retired Conductorr/Trainman and Yardmaster for the Boston and Maine Railroad. Brian Cummings Ma.
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Posted by Anonymous on Tuesday, December 16, 2003 11:20 PM
The name interlocking is rarely used anymore. The new terminology is Control Point which is basically the same thing. NS Central Division uses the term "control point" in issuing 23A Forms for MoW workers or highrailers.

Control Point and Interlocking are the same; meaning that it is controlled by a dispatcher via CTC(Centralized Traffic Control). The dispatcher controls the signals and switches within that Control Point or Interlocking. Of course also you have to put into play the priority of the train. If it is an Intermodal, they usually get top priority and the manifest or mixed freight get the bottom of the list.

Hope this helps.
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Posted by wabash1 on Wednesday, December 17, 2003 5:33 AM
control point refers to the signal that controls moves over the interlocking . a dispatcher is not in control of the interlocking and cant give permisson past this point. when giving the 23a he is giving it from the control point( signal ) to where the limits extend to. remeber when a 23a is given the limits must define exact locations ( fixed ) such as a street, bridge, mile post ,yard board etc. limits can be thru a interlocking . but other rules still apply for movement thru the interlocking.

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