Diesel Loco tail lights

[dj_crisp]

Hi

 

I've always assumed that both tail lights on a diesel loco would be lit.

 

However I've been flicking through a few photos of class 50s and can see that when stationary only one light is illuminated.

 

So now I've started paying more attention and noticed other classes have the same... so my questions are....

1. one tail light or two?

2. Is there different rules for running or stationary...

3. and do these rules apply for locos in the 90s?

 

Thanks for looking

Will

[25901]

A 24 or 25 can only have one light on as this is controlled by a two way switch that has a center off. There is a second switch but this puts on the drivers red marker on at the other end for lazy drivers

[Dagworth]

A 24 or 25 can only have one light on as this is controlled by a two way switch that has a center off. There is a second switch but this puts on the drivers red marker on at the other end for lazy drivers

47s and 86s were the same. I think most locos got modified late 80s/early 90s to make both lights come on together

 

Andi

[Swindon 123]

Up until the end of the 1980's the only train, and I include light engines in that category, that was supposed to carry two tail lamps was the Royal Train. Everything else should have only showed one tail lamp, including light locos. As has already been mentioned, on some locos it was impossible to light up both tail lamps  because of the type of switch used. Class 31's, 37's, 40's,, 55's, and 56's, could inadvertently have two tail lamps switched on as each lamp had its own individual switch, as I think class 20's did as well.

 

Paul J.

[dj_crisp]

Thanks all for your help.

 

It sounds like I should do my older locos such as class 50s with one lamp then... and keep my refurbished ones which happen to be 47s, 37s and 56s with two.

 

Is there a particular side that should be illuminated?

 

Thanks again

Will

[F-UnitMad]

Up until the end of the 1980's the only train, and I include light engines in that category, that was supposed to carry two tail lamps was the Royal Train. Everything else should have only showed one tail lamp, including light locos.

The InterCity125 HSTs showed two red tail lights, didn't they?

[Titan]

Originally only one.

[Dagworth]

Is there a particular side that should be illuminated?

 

whichever you want, just don't make them all the same...

 

Andi

[delticman]

The InterCity125 HSTs showed two red tail lights, didn't they?

 

As Titan said they only had one tail light illuminated, I know because as a youngster I fixed up a red grain of wheat bulb in my new Hornby HST to emulate this, only to melt a little of the corner of the nose. Looked quite convincing as a shunting swipe!

 

Geoff

[Torr Giffard LSWR 1951-71]

....the usual mistake with diesel tail & marker lights is to make them too bright. 1950/60s diesels (once the headcode blinds gave way to marker lights) had relatively dim instances of both.

 

Dave

[ForestPines]

Up until the end of the 1980's the only train, and I include light engines in that category, that was supposed to carry two tail lamps was the Royal Train. Everything else should have only showed one tail lamp, including light locos.

Didn't slip portions carry multiple tail lamps?

[andyman7]

I have to admit I did wonder at my memory when models started turning up with both tail lamps illuminated. I recalled the single lamp being lit and it's good to have it confirmed - the HSTs in particular as I also remember lashing up a Lima power car with a diode controlled single grain of wheat bulb for the backward direction.

 

I've just picked up the new Bachmann BR green/TOPS 47 - I think one of the LEDs is slightly misaligned as when running forward (i.e. in the direction with the fitted driver) only one tail lamp illuminates fully. In this case I think I'll leave it exactly as it is! 

[Swindon 123]

Yes HST's originally ran with one tail lamp lit. See

https://flic.kr/p/gCtAYT

https://flic.kr/p/iwJPx8

https://flic.kr/p/jH47Qv

https://flic.kr/p/qNLdRY

 

Around 1983 it would seem that they started to carry two tail lamps lit. It's possible that is when the change to two tail lamps being lit started as a requirement, although something in the back of my mind suggests it only applied to HST's at first.

https://flic.kr/p/BpeZTC

 

As to which tail lamp to light up, i always tended to switch the LH side one on.

 

Paul J.

[GordonC]

Were the scotrail push - pull 47/7s and DBSOs on the Glasgow to Edinburgh and Aberdeen services not an early exception to having two tail lights lit too?

[keefer]

the p-p cl.27s also displayed two tail lights, presumably the instruction was applied locally in the late 70s

 

https://www.flickr.com/photos/brianews/5768494765/in/album-72157626750951268/

 

unfortunately not dated, but the 27 still has a working headcode box

 

the 47/7s and DBSOs did use twin lamps, link to another thread which contained a pic of a DBSO in  january1980 - one tail light has failed so a tail lamp has been used in addition to the built in one:

 

http://www.rmweb.co.uk/community/index.php?/topic/2978-waverley-west-princes-st-gardens-and-haymarket-mpd/page-32&do=findComment&comment=964539

[russ p]

A 24 or 25 can only have one light on as this is controlled by a two way switch that has a center off. There is a second switch but this puts on the drivers red marker on at the other end for lazy drivers

Are you sure Robin? I can't remember what the later 25s were like but I looked after 5207 for several years and changed a red for a white as they were separately switched. This was supposed to be temporary as the previous owner had mullered the headcode wiring for a headlight..... Don't ask!

Aren't 24s six separate switches like a 20?

 

Green diesels didn't use them at all at first the railway not trusting them newfangled bulb things! I think it was about 68 that single red lights came into use.

 

DMUs didn't have red lights at all until about 1978, when built they were designed to have a red lense that would slip over the white markers but these were never used.

About 1978 they had a red bulb fitted in each outer marker lights as previously these had two white bulbs fitted.

[25901]

Are you sure Robin? I can't remember what the later 25s were like but I looked after 5207 for several years and changed a red for a white as they were separately switched. This was supposed to be temporary as the previous owner had mullered the headcode wiring for a headlight..... Don't ask!

Aren't 24s six separate switches like a 20?

 

Green diesels didn't use them at all at first the railway not trusting them newfangled bulb things! I think it was about 68 that single red lights came into use.

 

DMUs didn't have red lights at all until about 1978, when built they were designed to have a red lense that would slip over the white markers but these were never used.

About 1978 they had a red bulb fitted in each outer marker lights as previously these had two white bulbs fitted.

 

You've got me thinking now, it's that long since I saw our 24 as it's in storage due to blow gen but the 25/3s had centre off as I have a box of them under the stairs as well as a lot of cab fitting released from a ETHEL, must remember to send that lot to Devon soon for those two lol

[Edwin_m]

Were the switches changed later in the locos' lives, for those that survived that long, to allow both lamps to be lit together?  There's an obvious benefit to lighting both as the tail lamp is the last line of defence against a rear-end collision and the driver probably didn't have any indication that the lamp was still working. 

 

The other main purpose of the tail lamp was of course (and still is in the remaining Absolute Block areas) for a signalman to confirm a train is complete.  On a bright day it must have been quite hard to identify the rather feeble red light of the built-in version, and they may even have suffered from "ghost aspects" in low sunlight as signal lamps sometimes do.  So I wonder, when it became acceptable to use a built-in tail lamp, whether they were also made brighter to address this risk.  I seem to recall halogen lamps were new in the mid-70s and would have been an improvement over the traditional filament. 

[russ p]

What they did on 47s was put a bridge wire in so both lights illuminated in both the on positions on the switch then later on some replaced it with a single throw switch so both were on or off.

It's been nearly 30 years since I was on a 25/3 so can't really remember what they were like

[russ p]

Some of the 37s with the triple lamp clusters have very dim red lights that I often display a flashing one during the day. They are fine at night

[25901]

What they did on 47s was put a bridge wire in so both lights illuminated in both the on positions on the switch then later on some replaced it with a single throw switch so both were on or off.

It's been nearly 30 years since I was on a 25/3 so can't really remember what they were like

 

Left switch is a 25/3 marker light one (center off) and the right one a standard on/off fitted to same loco's

[russ p]

The centre off one looks the same as a railcar one

[Steadfast]

The 59/0s still have independent control of each tail light. Were these the last locos built with this control? And are they the last to retain this ability?

 

Jo

[russ p]

56s probably still have separate switches, it's a couple of years since I last drove one but that had them.

[roythebus]

55s could only display one tail light. The Rule Book requirement was for one tail light only, except the Royal Train. Goods trains displayed one red tail light but also had the side lights which displayed white towards the front of the train so the loco crew could see the train was complete. ISTR they showed side red lights to the rear. 

 

SR EMU stock fitted with low voltage lighting (EPB stock onwards) used red binds as there was a battery standby supply if traction current went off, SUB/BIL/COR etc used line voltage for lighting and NO battery back-up so had to use oil tail lights. Same on LT, pre 1938 and COP stock used line volts for lights so required an oil lamp. Later stock had battery supply for the tail lamps, so no oil lamp required. We had to use the oil lamp on COP stock when running over BR as they did not accept one electric tail light on LT stock. We rarely lit the oil lamps though!