I was reading about railroad rules at Al Krug’s site. Very interesting!
http://krugtales.50megs.com/rrpictale/rules/rule_eleclock.htm
The site talked about a hand-operated electric lock switch that had a 7 min. wait period. I got the impression that you couldn’t throw the switch if the train wasn’t right next to it. It also mentioned about unlocking the switch but not thowing at that time.
Will somebody explain about this type of switch, how it is used, and how it works.
An electric locked switch and an electric locked switch timer are two different things but may be used together. An electric locked switch is a hand thrown switch the electric lock being controlled by a dispatcher or an operator at a distant point. The timer, more prevelant at interlockings switches, is so that after unlocking there is a waiting time before the physical change can be made to determine if there are other trains approaching before the movement fouls the swithch. I’ve heard it is also used to give crews time to think through their move. That usually occurs when a movement is altered or changed after a signal governing the switch has changed it’s aspect. If a train is a block or two away, it has to react to signals dropping in front of it, i.e. from clear to approach or clear or approach to stop. Thus the time allows for safety.
So the act of unlocking the switch affects the signal system thus showing other trains the intention to change that switch even though you cannot actually change it for several minuits. Right?
Sorry this is long, but like just about everything in signaling, there’s a lot of detail. Electric locks appear in signalled territory, both CTC and ABS-TWC or ABS-DTC. The preponderance are in CTC territory.
An electric lock as the term is now used in AREMA standards is a device to prevent a hand-operated switch in controlled-track territory from being opened until the controlled signals governing main track movements over the hand-operated switch are at STOP and not running in time, and no train is in the block containing the hand-operated switch (between the controlled signals) unless the train is detected as moving away from the switch. The electric lock is not dispatcher controlled; is is 100% local.
In other words, the electric lock prevents the opening of a hand-throw switch in signalled territory in front of a train, and runs time on the signals so that an approaching train has time to clear the block before either the switch is thrown in front of it and without putting up an unanticipated red signal in front of a train. Regardless, authority from the train dispatcher is still required to enter the main track.
The method of operation of an electric lock for a train entering the main track at an electric lock is as follows:
The train must first have authority to enter the main track. The authority is granted by the dispatcher. To grant that authority the dispatcher must first protect conflicting train movements. The dispatcher must do this by either setting adjacent controlled signals at stop, or verbally directing the conflicting train to stop AFTER requesting from the conflicting train if it can stop safely. The electric lock is just a signal-system interlock on all this, that there’s not a train already in the block that cannot stop safely before it encounters the open switch (or the train that might emerge from it!). It sets adjacent controlled signals to stop, approach-locks them, and aspects on either side of the controlled signals tumble down appropriately from proceed to approach, etc.
RWM
Basically, and simply, yes. It is interlocked to the signal system: either the act of unlocking affects the signal system or the dispatcher/operator has to set the signals in order to unlock the switch. But as RWM points out, there are many variables and situations so that each electric lock switch and each lock timer is its own universe.
Dispatchers don’t set signals, they only make requests to the signal system. The signal system grants the request only if it deems it safe to do so.
This may seem like a semantic or technical point but this distinction is absolutely fundamental to the logic of signal systems and train control method, and getting it backward means that virtually everything about train controls and signaling will make no sense. The entire point of an automatic system is that people do not control it because people make mistakes. I have spent now going on 30 years explaining over and over and over and OVER to people why this matters, and they just look at me like I’m speaking gibberish. The point is this: If unsafe conditions are caused by people that make mistakes, and we want to create a mechanical system that keeps people from making mistakes, why on earth would we then guarantee the system will fail, the system we just spent all that money to build, by allowing people to mess around with it? I think perhaps people took the Wizard of Oz too seriously and really do believe that
…Now you know why trainmen and some maintenance guys look like they’re faith-healing/laying hands on the solenoid housing waiting for the thing to clunk and release. I’m wondering if Mr. 7 Minute unintentionally started the time-out process all over again?
I have heard of all kinds of ungodly times on these things…up to 15 or 20 minutes in fact. Ordinarily they are in the 5 to 10 minute range. I have also heard of the timer clocks being smashed by a train or signal or tower man because of bad moves or total impatience…
This has been a fascinating thread. I just wanted to add that the basic concept being discussed is very old. I have read of diamond crossings on the Canadian prairies where when one train approaches the crossing, the crew either flips a switchstand type signal with a kerosene lamp on top or lights a fixed lamp and then sits there for a fixed number of minutes (not many in a world of 25 mph railroading) before he can cross the diamond. Then after the train has crossed the diamond the tail end trainmen either turns the lamp to its’ original position or extinguishes it.
I always enjoy these types of discussion where you can see modern solutions to problems that have existed since the second train was put on the tracks.
AgentKid
It certainly has been fascinating and informative. I have known of electric locks for more that fifty years, from studying employee timetables and a few other sources, and I understood that their purpose was to enable any approaching movement to clear the switch or crossing before it would be fouled by the movement that needed permission to enter the main or move across the other main. RWM’s posts explain the systems so that any of us non-railroaders should be able to understand their workings.
Johnny
Photo of one (not the most illustrative, unfortunately) - it’s the silver boxes down on the switch timbers and the silver post next to the switch stand, to the right of the BNSF locomotive:
http://www.railpictures.net/viewphoto.php?id=146303
and a manufacturer’s catalog pages for 2 models at:
http://www.alstomsignalingsolutions.com/OurProducts/WaysideProducts/SwitchProducts/Locks/
Another 3, from Ansaldo (formerly Union Switch & Signal, until Jan. 1, 2009):
See also Rules 10.1 and 10.2 as scanned and reprinted from the 1994 General Code of Operating Rules at:
http://www.psrm.org/faqs/rulebook/ctc.html
Paul why dont you exsplain 10.0 10.1 10.2 10.3 and 10.3.1 10.3.2 10.3.3
B. I figured Railway Man essentially did just that for 10.1 and 10.2 in one of his posts above, far better than I could. And 10.3 - Track & Time and it subsections are really beyond the scope of electric switch lock operations.
iii. The rules are supposed to be self-explanatory and comprehensible by reasonable people of normal intelligence, right ? So I also think anyone that wants to know more can read and study those rules for themselves. Of course, it always helps to have someone knowledgeable and experienced with them rules - or any technical subject, for that matter - to serve as a guide and point out the weak spots and traps for the unwary, etc. So is there anything you want to say about them ?
The ability to comprehend and communicate is vital when working for a railroad. We have seen this discussed on other threads. Anyone who has anything to do with the movement of trains and the maintenance of everything connected with the movement of trains must be able to comprehend and communicate–for the safety of all who are concerned with such.
It is true that it is difficult to state some directions concisely and clearly, and, as Paul remarked, the employee who has some difficulty understanding the direction or rule must rely on another employee who is familiar with it–and can communicate his knowledge.
wabash1, I agree with Paul; I am sure you could explain all of these rules so that even he can understand them.[:)]
Johnny
To reiterate: those whose job it is to do also know. They are instructed, have books of rules, classes, timetables, bulliten orders, and tests, reviews and more tests. To fully know, understand, and operate under the rules and regulations is both mandatory and necessary for both holding down the job and for one’s own personal safety as well as the safety of other employees, the employers property, the employers’s customers products, and the general public. Failure to know and follow these rules and procdures could result in loss of job even loss of life. Railroaders are not stupid people by a long shot, they have to study and study hard, be prepared for changes, and be alert at all times. Not 9-5 mentality by any means.
No i was not pulling your leg. But due to the moderators altering my post or deleting them I will refrain from pursuing this topic for clairifacation.
That is indeed unfortunate; both your posts getting altered, and your not posting for clarification.
wabash1 - and others -
I don’t think that I’m qualified to explain these rules in detail any better than has already been done here above, by RWM and others. However, I just had an opportunity to review the essay by Al Krug that started off this thread.
It’s on his “Tales From The Krug” page, titled “GCOR Electric Locked hand operated switch rule”, and can be found at:
http://krugtales.50megs.com/rrpictale/rules/rule_eleclock.htm
He discusses several different scenarios in CTC terrritory involving electric locks during the pick-up of a loco from a facing point spur, yarding a too-long train from a main line with another train waiting, and running around a cut of tank cars to be spotted at a facing point spur, all revolving the interpretation of the critical word “ENTER”. Most of us here should find it informative on the nuances of this; you working rails will likely find it amusing as well, particularly Krug’s comments on the interpretation of “Rules” by railroad officials at:
http://krugtales.50megs.com/rrpictale/rules/rules.htm
Huh?