# Marker Lights



## iceclimber (Aug 8, 2010)

On some Steamers, like the Pennsy K4 Prewar (pre front end modernization) Marker lights on the Pilot were sometimes Amber on two lenses and Red on the other lenses and the markers on the Smoke box were green all around. What was the reasoning behind the colors. Tender Markers were Red all around.


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## Gary Armitstead (Jan 2, 2008)

Jeremiah,

I believe the lamps you are talking about (on the FRONT of the engine) are called Classification Lamps, not marker lamps. I'm really not sure exactly what the colors mean, but you might want to "Google" Classification lamps.


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## iceclimber (Aug 8, 2010)

Really? I always thought the classification lights were the side lettering on the headlamp which illuminated the road number. From anything I have ever read, the lights atop the pilot and smokebox were called marker lights. 1361 of the PRR K4S Pacific had tombstone style markers where as the pre-modernized K4s had the lights with 4 lens. I'll do a search on classification lights though. THanks.


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## Andre Anderson (Jan 3, 2008)

Greetings,

Well what you have are two different kinds of lights. The ones on the smoke box or front of the locomotive are called classification lights would be used in one of three following situations. First the lights are off, this tells other trains that are meeting this train that this train is on the schedule. Second situation is with them showing green or carrying green flags during daylight hours, this tells any train that this train meets that there are more sections following this scheduled train, what this means that the train in the siding must wait till all of the sections of the scheduled train passes. I can not say for sure with the Pennsy but for example on the SP they would display the train number in the number boards and if there were more than one section you would see something like this 1-99 on the first section and 2-99 on the second section and if there was a third section it would display 3-99. Now in this case the first and second section would have green lights or flags displayed indicating that there was another section following, the third section would not have any classification lights or flags displayed so that other trains would know that this was the last section of a scheduled train. The third situation is if the train is an extra and then it would display either white lights at night or white flags during the day. This train is not on the schedule and must with time table operations stay out of the way of all trains on the schedule. This can be modified by train orders issued from the dispatcher but this is a whole new can of worms.


The lights on the tender are called marker lights and should only be lit if the locomotive is running light, IE with out any cars behind it. The reason for this is that a "Train" is defined as "A locomotive with or without cars that has the right to occupy that section of track, this right can be granted either by schedule or train orders and displaying marker lights on the rear of the tender or last car signaling the end of the train. The reason for this goes way back to the time before air brakes and radios, For example you were the engineer of a locomotive and you had pulled in to a siding to wait for a superior train and it came along you would know if the whole train had passed you if you saw the rear marker lights on the last car. This is why on some railroads the marker lights showed red in all directions and some showed amber. Before air brakes or radios the train could break in two and the locomotive engineer would not know because there would be no drop in pressure and no radio meant that the conductor in the caboose could not tell him that the train just broke in two. Now a good engineer would notice that his locomotive was not pulling on the grades as hard as it should and would probably stop to check things out. Your K-4 would only show red marker lights if it was traveling light, two examples would be, first running from the servicing facility to the passenger station to pick up it's train and second if it had been used as a helper locomotive and it was returning down grade from the summit to the base of the helper district, there may be other situations but these would be the most common.


I hope this helps,


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## Gary Armitstead (Jan 2, 2008)

I did a Google Search as I had suggested and this came up first.









http://trn.trains.com/en/Railroad%2...ights.aspx


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## iceclimber (Aug 8, 2010)

I see, that definitely clears things up a bit. Thanks all.


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