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View Full Version : Classification lights - exactly how useful were they?



Chris750
December 10th, 2014, 12:10 PM
Reading about classification lights and how white meant it was an extra train, green meant extension following. Ok, but what exact use would this be of? So I approach another train and I see white classification lights, what effect would this have on me? In simple terms...why would I care?

I guess if there were follow up trains (green) the other train would know they have to sit on a siding longer, waiting for the followup train(s) to pass, but if white?

Just curious. Read why they have them, but not really why one would care.

JCitron
December 10th, 2014, 12:13 PM
You might find this helpful.

http://cs.trains.com/trn/f/111/p/238257/2658899.aspx

White is an extra, or special while a green is another section, and red is last section or end.

John

Chris750
December 10th, 2014, 01:13 PM
I read that, along with a few other articles before posting all of which tell what they mean but not why another train would care. I see a train approaching, it has white classification lights meaning an extra or not on time table...so what? That is probably why they don't use them anymore.

JCitron
December 10th, 2014, 01:22 PM
I read that, along with a few other articles before posting all of which tell what they mean but not why another train would care. I see a train approaching, it has white classification lights meaning an extra or not on time table...so what? That is probably why they don't use them anymore.

In the old days when there were many, many trains running I suppose they made a difference, but today I agree who cares since the traffic is so infrequent. In my area the commuter trains are run as extras on the freight lines, meaning they have to receive permission to operate over the lines instead of having a priority over the freight traffic.

John

cascaderailroad
December 10th, 2014, 02:47 PM
On Felix_G's locos I was having a terrible time with the class lights showing up. they were all white ... I solved the problem by copy / pasting all the class light images, and text files, into all of his related loco's ... now they all show up just GREAT !

norfolksouthern37
December 10th, 2014, 03:33 PM
In the old days when there were many, many trains running I suppose they made a difference, but today I agree who cares since the traffic is so infrequent.

no no no. for one, traffic today can be as frequent or even more than it ever has been in any one area of a railroad in america. it has to do with timetable and keeping to it. the reason there is no use for class lights today is that there are no timetabled freights anymore.

here is an example: your train is supposed to wait in the siding for train 20 but today train 20 is in 2 sections. you need to be able to identify both sections of 20 in order to satisfy your orders. so you would see train 20 first section come with a green indicator. or maybe there is another train that isnt on the timetable - that one is marked with white. this is important because you would need to know it isnt another train that you would assume to be late or early. when timetables were important to be kept to so that traffic would move freely over a line these were very important meanings. certain trains were scheduled to meet other trains at certain times, so any addition of extra trains or following sections could potentially upset this timetable if not clearly indicated.

SharkNose
December 10th, 2014, 08:09 PM
<snip> the reason there is no use for class lights today is that there are no timetabled freights anymore. <snip>

And I thought classification lights were for passenger trains only.

When CSX has a second section for a train, the first would have the symbol Q174-10 (the "10" indicates the day of the month) for example and the second section would have the symbol X174-10.

Andrew

Ricke82
December 10th, 2014, 08:11 PM
...any addition of extra trains or following sections could potentially upset this timetable if not clearly indicated.

More importantly, they could also result in a head-on collision. You need to remember that timetable/train order authority was used before there was radio communication with the train or automatic signaling/centralized traffic control on most lines. Once the train left the station the only information it had regarding other trains on the track was what was in the timetable or a written train order. To use norfolksouthern37ís example, if you had not been notified that Number 20 was in two sections or that the dispatcher had slotted an extra in ahead of it when you left the station there was no way to contact you and to let you know that once you were out on the line. Class lights/flags were used to convey that information and thus avoid a cornfield meet.

Chris750
December 10th, 2014, 10:03 PM
Excellent, NorfolkSouthern37 and Ricke82 answered my question and it now makes sense, especially the waiting on a siding for train ## which comes by you with green lights so you know more is to follow until you see red.

As for white lights, how would this be handled? I am train 20 on a scheduled time table and I am on a siding and then train 66 with white classification comes along (not on time table or schedule, in effect a 'ghost' train)...ok, so what does this mean or how does it affect me?

Thanks for the replies guys, even all the articles online didn't answer this.

mjolnir
December 10th, 2014, 10:09 PM
Friends,

I tried a couple of times to write what NS37 wrote, but ran out of time, and besides he did it better than I would have, anyway. I would add though, that class lights were developed, and were critical in days before communication. Today, if a crew were waiting in a siding, and needed to know what the train that just passed them was, they'd just get on the radio with the dispatcher and ask him.
But when class lights (and during the day time, flags, of the same color) were developed, there were no radios. All the crew had to go by was the time table, the standard time piece, and the information on the train they were wondering about itself. If train 231 had been sidelined earlier the schedule with a "hotbox", and a dispatcher let X4532 out ahead of it because of the delay, and X4532 got to the point where a crew was waiting for 231, the class lights on X4532 was not 231.

ns

Ricke82
December 10th, 2014, 10:11 PM
You know it's an extra and not the train you are to hold on the siding for. You will continue wait on the siding for the that train (and any sections) and only proceed when it has passed.

Chris750
December 10th, 2014, 10:15 PM
So I think I have it figured out:

1. Train A is using his time table and knows train B will be passing at a siding at 1400. At 1400 train B comes by with green lights so train A knows to wait until train B part 2 comes by with red lights.

2. Train C is an extra with white lights. He has a time table too but must yield to all others on the route according to the time table, so he may have to pull into a siding and wait for train B to pass with red lights and then he can proceed. Train B, so he doesn't go "who the hell is that when they aren't on the table" will see the white lights and know he didn't screw up and will just carry on.

Roger dodger??

mjolnir
December 11th, 2014, 12:34 AM
Chris:

One thing about your statement:


He has a time table too but must yield to all others on the route according to the time table, so he may have to pull into a siding and wait for train B to pass

An extra train is created by, and moves only upon the positive direction of train orders issued by the dispatcher, so it would be better to say that the extra train will pull into the siding the dispatcher directs. The train does not run and pull into the siding it chooses to pull into, except that if the train is out of communication with the dispatcher, and is running late, the train must be in a siding some interval of time defined by the rule book or special instructions before the time that the next train in either direction is due to to arrive at that station.

Second,


train B comes by with green lights so train A knows to wait until train B part 2 comes by with red lights

red classification lights are displayed on all sections, but visible only to the rear, and only when the train is on the main track. When not on the main track, red classification lights are changed to white.

ns