Exiting a depot onto the mainline (Signals?).

[40034_Nick]

Hi All. when exiting a depot under a bridge in this case onto a mainline (Or the fiddle yard in my case). Would there be signals involved and if so before the bridge? (red and green i guess).

Sorry for the maybe silly question but i have no clue in this case :-(

 

Thanks

 

Nick

[Dagworth]

Every depot I’ve ever encountered the exit signals have been ground shunt signals. In my era always position light signals, in some cases with a yellow rather than red stop aspect. (Slade Green had yellow on the down exit allowing access to the headshunt) 

 

I don’t recall any depot where you left under main aspects. 
 

Andi

[Mark Saunders]

Leeds Midland Road is entered with a Ground Position Light and exited on a Main Aspect.

[40034_Nick]

Ok great..

 

These things ? https://www.dccconcepts.com/product/4x-2-wire-diesel-era-3-light-ground-signal/

[Andymsa]

There is not a definitive answer to the question for exit signals from depots, for example Ilford on the great eastern has main aspect signals for leaving a depot, where as Southend Victoria has a position light. The difference is at Ilford your proceeding on a main line so you would need to know what the next main aspect is, where as at Southend your going into a platform so no main aspect is needed. So the answer is location location location

[St. Simon]

55 minutes ago, Andymsa said:

There is not a definitive answer to the question for exit signals from depots, for example Ilford on the great eastern has main aspect signals for leaving a depot, where as Southend Victoria has a position light. The difference is at Ilford your proceeding on a main line so you would need to know what the next main aspect is, where as at Southend you’re going into a platform so no main aspect is needed. So the answer is location location location

Nope, the answer nowadays is operations operations operations.

 

The choice between main and independent position light is down to whether operations can live with the train going at very slow speed from a position light to the next main aspect. If yes, position light, if not then main aspect. That can be based on a number of factors, distance to next main aspect, sighting of next main aspect, platforms etc etc.

 

However, the principle in days gone by was position lights always unless you really really needed a main aspect.

 

1 hour ago, 40034_Nick said:

Ok great..

 

These things ? https://www.dccconcepts.com/product/4x-2-wire-diesel-era-3-light-ground-signal/

That type of signal yes, but don’t use those, they are very overscans (particularly twice the size needed for O gauge!)

 

Simon

[St. Simon]

1 hour ago, Dagworth said:

Every depot I’ve ever encountered the exit signals have been ground shunt signals. In my era always position light signals, in some cases with a yellow rather than red stop aspect. (Slade Green had yellow on the down exit allowing access to the headshunt) 

 

I don’t recall any depot where you left under main aspects. 
 

Andi

Hi,

 

Just to point out that Yellow Shunts are now banned for new works, but you can find the odd one left.

 

Simon

[Michael Hodgson]

19 minutes ago, St. Simon said:

Hi,

 

Just to point out that Yellow Shunts are now banned for new works, but you can find the odd one left.

 

Simon

Also the description "Diesel era  Blue till now" isn't quite right either - though you can still find the odd one left.  The pivot light (the right-hand one) these days is generally red when the signal is on, white when off; it would have a cold white tint.

[40034_Nick]

40 minutes ago, St. Simon said:

That type of signal yes, but don’t use those, they are very overscans (particularly twice the size needed for O gauge!)

 

Simon

 Ok thanks... Which do you suggest ?

[phil-b259]

2 hours ago, 40034_Nick said:

Ok great..

 

These things ? https://www.dccconcepts.com/product/4x-2-wire-diesel-era-3-light-ground-signal/

 

TOTALLY WRONG!!!!

(And DCC concepts should know better)

 

Firstly, assuming the ones on the left are supposed to represent post 2002(ish) shunt signals (i.e. the modern LED units) then with the exception of a few very early installations every single one has two horizontal reds for stop / danger - not one red and one white.

 

Secondly the ones on the right lasted right up until the early 2000s - NOT the 'blue diesel era and as such would be the ones modellers need to use not only for sectorisation era layouts but also for early privatisation ones as well.

 

(Note the large bold text is done to match the boldness of the text in the images rather than an attempt to be aggressive. When such incorrect statements are so prominently featured the rebuttal of them has been made large for physical visibility on the screen / page and should not be taken as anger against anyone)

 

Edited November 16, 2022 by phil-b259

[40034_Nick]

I am modelling 1982-4 in Scotland BTW

[40034_Nick]

2 minutes ago, phil-b259 said:

 

TOTALLY WRONG!!!!

(And DCC concepts should know better)

 

Firstly, assuming the ones on the left are supposed to represent post 2005ish shunt signals (i.e. the modern LED units) then with the exception of a few very early installations every single one has two horizontal reds for stop / danger - not one red and one white.

 

Secondly the ones on the right lasted right up until the mid 200s - NOT the 'blue diesel era and as such would be the ones modellers need to use not only for sectorisation era layouts but also for early privatisation ones as well.

 

 

What do you suggest ? This is getting so confusing ..

[phil-b259]

23 minutes ago, 40034_Nick said:

 

What do you suggest ? This is getting so confusing ..

 

The traditional colour light shunt signal featuring one red and one white light to indicate 'stop' / 'danger' / 'on' stems from the fact that some shunt signals were required to have lamp proving (i.e. circuitry which proves tit to be lit to the signaller). This was done by having one white light illuminated at all times (known as the 'pivot' light) even though it gave a less than ideal 'stop' indication

 

This design was used for many decades - the earliest examples being installed under a LNER scheme) and continued in use throughout the BR era - be it steam, green diesel, blue diesel, sectorisation - and even early privatisation eras - hence the captions are utterly misleading.

 

Also, these signals were ALWAYS fitted with filament lamps - NOT LEDS so a 'warm white' LED should be utilised when portraying them in model form.

 

However, the downside of these traditional shunt signals is that if the red lamp fails then you just get a single white light showing when the signal is at 'stop / 'danger' / 'on' - and that is asking for drivers to pass the signal when they shouldn't.

 

As a result, trials started in 1996 of a new LED shunt signal which had both red and white LEDs mounted into the same 'lamp' this allowed two reds to be displayed as a 'stop' / 'danger' / 'on' indication meaning much less chance of a driver passing them when they shouldn't

 

Unsurprisingly feedback was very positive and Railtrack lots no time in getting their contractors to replace the old filament style 'red + white' = 'stop' / 'danger' / 'on' signals with these new LED equivalents.

 

Now its true that initially there was a problem as the LED design did not allow for lamp proving so where this was a feature of existing signalling installations you did get some 'red + white' = 'stop' / 'danger' / 'on' signals being used for a short while 

 

BUT this was recognised as undesirable given the better readability of two reds as a 'stop' / 'danger' / 'on' indication so the manufacturers quickly tweaked the internal design of the LED shunts so they would be able to support lamp proving with these revised units replacing the earlier 'red + white' = 'stop' / 'danger' / 'on' signals as soon as possible 

 

Thus NEITHER of the two signals pictured is suitable for the post 2002(ish) layout and the one on the left was only ever installed in a few select locations for a short timeframe. The one on the right however is good for a lot longer than the caption sugests...

 

Edited November 16, 2022 by phil-b259

[St. Simon]

38 minutes ago, 40034_Nick said:

 Ok thanks... Which do you suggest ?

Hi,

 

The Eckon versions are the right size, but fairly fiddly to build, I’m not sure whether CR Signals still make theirs, but they are good and you’ve got Absolute Aspects, which are good but slightly expensive.

 

Simon

[phil-b259]

32 minutes ago, 40034_Nick said:

 

What do you suggest ? This is getting so confusing ..

 

As Simon says the choice of exit signal is determined by the requirements of train operations - not some rigid 'it must be this' requirement.

 

Therefore, as with 99% of models you must consider the 'imaginary world' byeond the confines of your layout - as this will guide you to the correct solution. i.e. Does your yard lead out onto a busy main line? how far would a train exiting the yard have to go before encountering another signal*, is the main line fitted with 2, 3 or 4 aspect signalling**, etc

 

 

* doing 10mph - shunt signals even when telling a driver they may proceed only say the route is set for them, they don not guarantee the line ahead is clear of other trains so the driver must proceed at caution. Traveling at caution for 2 miles takes an awful long time...

 

** You NEVER get a situation where a driver can go from a green straight onto a red aspect. So if the mainline is fitted with 3/4 aspect signalling then the yard exit must also feature a 3 / 4 aspect signal

 

[St. Simon]

4 hours ago, phil-b259 said:

So if the mainline is fitted with 3/4 aspect signalling then the yard exit must also feature a 3 / 4 aspect signal

 

To clarify, that is only if a main aspect is provided out of the yard, if a position light is provided, the same type is provided regardless of what aspect signalling is on the mainline.

 

4 hours ago, phil-b259 said:

** You NEVER get a situation where a driver can go from a green straight onto a red aspect.

 

 

I think you technically could if it was within Station Limits and being worked in Absolute Block working, I would have to check the principles on that.

 

Simon

Edited November 16, 2022 by St. Simon

[phil-b259]

16 minutes ago, St. Simon said:

 

I think you technically could if it was within Station Limits and being worked in Absolute Block working, I would have to check the principles on that.

 

Simon

 

True - if you had a situation where the signal heads were simply changed from mechanical / semaphore to colour lights (or an extra colour light added into the mix as part of a minor layout change) but Absolute block was retained.

 

However for decades such a 'mix'n match' has not been permitted to be newly created - and thats why we have seen NR actually building new semaphores where Br might have just put up a colour light.

 

[St. Simon]

Just now, phil-b259 said:

However for decades such a 'mix'n match' has not been permitted to be newly created - and thats why we have seen NR actually building new semaphores where Br might have just put up a colour light.

 

 
There’s nothing in the standards that prevents it as far I can remember, just it is non-preferred (the only thing I think is that if you do it, you have ensure the semaphores have intensified lights). I have done at least 3 jobs in the past 8 years that involve changing a single semaphore for a colour light :) 

 

Simon

[phil-b259]

4 minutes ago, St. Simon said:

 
There’s nothing in the standards that prevents it as far I can remember, just it is non-preferred (the only thing I think is that if you do it, you have ensure the semaphores have intensified lights). I have done at least 3 jobs in the past 8 years that involve changing a single semaphore for a colour light :) 

 

Simon

 

Were those locations already 'mix'n match' locations? If things are already a muddle then one more isn't going to hurt.

 

Banbury got new semaphores a decade ago (while the place was still mechanically signalled) to facilitate turnbacks of GWR services during electrification and several other locations like Turo and Worcester saw new semaphores provided rather than colour lights...

[St. Simon]

Just now, phil-b259 said:

 

Were those locations already 'mix'n match' locations? If things are already a muddle then one more isn't going to hurt.

 

Banbury got new semaphores a decade ago (while the place was still mechanically signalled) to facilitate turnbacks of GWR services during electrification and several other locations like Turo and Worcester saw new semaphores provided rather than colour lights...

 

No, none were mix and match apart from colour light distants (but then had semaphores in between that and the new colour light)

 

Simon

[40034_Nick]

5 hours ago, St. Simon said:

Hi,

 

The Eckon versions are the right size, but fairly fiddly to build, I’m not sure whether CR Signals still make theirs, but they are good and you’ve got Absolute Aspects, which are good but slightly expensive.

 

Simon

 

I bought a Eckon one a while back and wasnt happy as there is way too much white bleed into the off red light..

[JeffP]

9 hours ago, 40034_Nick said:

 

I bought a Eckon one a while back and wasnt happy as there is way too much white bleed into the off red light..

Resistor in the red feed?

Sleeve or paint the sides of the bulb?

[JeffP]

Reading this with interest.

Sorry if it's s bit off track, (see what I did there?), but what of railway works, especially the larger ones.

Did they have any signalling? If so, who controlled it and what was it like?

[The Johnster]

Within railway workshops, ‘yard’ rules applied; hand operated turnouts and movements under the control of staff on the ground.  Despite the size of some of these places, there was not much movement in these yards.  Leaving them on to running lines or arriving from running lines was a similar procedure to loco sheds. 
 

Rules may well and probably have changed since my day, the 70s, but the speed of a movement controlled by a shunting or other subsidiary signal was ‘under caution’ which we were told meant ‘at a speed consistent with the driver being able to stop the locomotive or train within the distance he can see and confirm that the line ahead is clear’, in other words something like driving a road vehicle safely.  Speeds much higher than 10mph could safely be used so long as the driver could clearly see that the line ahead was clear and was able to stop within that distance.  Unless he is proceeding under a main aspect, he must assume that thr section ahead is occupied and drive accordingly, but this does not necessarily mean snail-racing.  Speed within yards and on permissive block running lines was restricted to 15mph, and in loco yards locos could move without being handsignalled by staff on the ground; you sounded the horn and looked around before moving. 
 

The usual arrangement leaving sheds was to  phone the signalman from the exit ground signal and identify the working; ‘light engine off shed please, officer, for 7M49 03.15 Cardiff Long Dyke-Carlisle’.  Coming on shed one would arrive by a calling-on aspect and pull up at a STOP board or the queue for one.  Depending on the layout of the place the loco might be left in ‘engine only’ with the handbrake on and AWS isolated for shedmen to deal with (Canton), or you phoned the shed foreman from the STOP board (‘light engine off xxxx) and he would tell you where he wanted you to leave the loco.  In either case, the driver formally handed the loco over in the foreman’s office by handing him the repair book; collecting a loco was a reverse of this; ‘4E11 00.35 Peterborough Parcels? 7098 on 5, driver, here’s the book’. 
 

 

Edited November 18, 2022 by The Johnster

[John M Upton]

Littlehampton Yard Carriage Sidings has a yellow ground shunt signal, two horizontal yellows and you are off up the unelectrified headshunt (until you run out of power), two diagonal whites and it into the station, platform 1 only as it is the furthest exit, the other has a conventional red/white shunt signal.

 

The whole area is being resignalled next year so I am not sure if it is being binned, it is the only one on our turf down here.