Signalling advise required

[sulzer27jd]

I'm looking for some advise on the signalling for Balbeggie Sidings. In particular the exit from the loops at the sidings themselves;

 

 

In the above diagram where the two loops converge and then rejoin the main line (just ahead of the level crossing).

 

My question is, would each loop require to be signalled or would 1 signal on the short section between the points be sufficient to let trains exit the loops?

 

Any help appreciated.

 

John

[Guest stuartp]

It would depend whether the two loops are running lines or not. If they're running lines (i.e. under the direct control of the signalbox, all points worked from the box, no moves without the signalman's permission), then I would suggest each loop would need an exit signal otherwise the signalman has no means of making it clear which of two adjacent trains has permission to move. However, if, as I suspect is the case, the loops are part of the sidings, (i.e. handpoints, movements controlled by the shunter once inside, only the points onto/off the mainline controlled by the signaller), then one signal would suffice. Whether this would be a yellow disc, single disc reading both ways (mainline/headshunt) or two discs stacked on above the other would depend on installing company practice.

 

Out of curiosity - the inner curve at the right hand end - is it part of the main line, e.g a goods line or loop, or part of the sidings, e.g. the NCB/private line from Balbeggie Sidings to Kingslaw OLF ?

 

Interesting plan btw, loads of operating potential !

[sulzer27jd]

It would depend whether the two loops are running lines or not. If they're running lines (i.e. under the direct control of the signalbox, all points worked from the box, no moves without the signalman's permission), then I would suggest each loop would need an exit signal otherwise the signalman has no means of making it clear which of two adjacent trains has permission to move. However, if, as I suspect is the case, the loops are part of the sidings, (i.e. handpoints, movements controlled by the shunter once inside, only the points onto/off the mainline controlled by the signaller), then one signal would suffice. Whether this would be a yellow disc, single disc reading both ways (mainline/headshunt) or two discs stacked on above the other would depend on installing company practice.

 

Out of curiosity - the inner curve at the right hand end - is it part of the main line, e.g a goods line or loop, or part of the sidings, e.g. the NCB/private line from Balbeggie Sidings to Kingslaw OLF ?

 

Interesting plan btw, loads of operating potential !

 

Thanks stuartp - the inner curve is part of the main line and is used for access to the sidings and loops. The loop nearest the main line is regarded as being a loop and is used to hold freights. The other loop tends to be used more as a siding, giving access to the small yard but can, and does function as a second loop. The exit will be controlled by the signalman (it would be the Edinburgh power box I think) so I guess they each require signalling.

 

thanks

 

john

[Guest stuartp]

Thanks John. Unless Beast, Stationmaster or any of the other signalling guru's know better, then I'd say yes you need them both separately signalled.

[The Stationmaster]

Thanks John. Unless Beast, Stationmaster or any of the other signalling guru's know better, then I'd say yes you need them both separately signalled.

 

I know no better All sounds quite ok thus far and I go along with the 'separate signal' method for the way the layout and operations have been described.

[Edwin_m]

I agree if the second loop is used to refuge trains passing through the area then it would almost certainly have an exit signal and also an appropriate route indicator on the signal that controls moves inwards.

 

Normally the signals controlling the two loops would be alongside each other but if a long train in the first loop (nearer the main line) needs to stand over the exit points from the second loop then the signals couldn't be in line. In this case I think when a route was set out of the second loop then the first loop would have to be empty and both loop exit signals would show the same aspect. However I don't recall any such situation on the prototype - perhaps one of our experts can comment? I'm also wondering whether the second loop would have a trap at the exit to protect against shunting moves overrunning into the first loop.

 

The small set of sidings I'd suggest would be on a ground frame with no signals. This would be released by the signalbox when shunting was required, and moves controlled by hand signals.

 

If there was no main line signal (for the same direction) in line with the loop signals then the loop signals would probably be approach lit. They would show no aspect at all unless either a route was set into that loop or the loop itself was occupied. This is to avoid the loop signal causing confusion to drivers on the main line. The loop approaching Inverkeithing from the Aberdour direction had this arrangement when taken over by Edinburgh power box around 1980 and it was common on other Scottish power signalling schemes of the time. It would be a good talking point for the layout when people say "your signal has gone out!".

[sulzer27jd]

Thanks all.

 

I had planned to have the main line signalled at that point but I do like the idea of approach lit signals for the loops.

 

Mmmmm? Got me thinking now.

 

thanks again

 

J

[Edwin_m]

You could have the main signal just before the points where the first loop converges and both the loop signals further back just before they converge with each other. That would probably be far enough apart to give you an excuse to approach-light the loop signals.

[The Stationmaster]

 

 

Normally the signals controlling the two loops would be alongside each other but if a long train in the first loop (nearer the main line) needs to stand over the exit points from the second loop then the signals couldn't be in line. In this case I think when a route was set out of the second loop then the first loop would have to be empty and both loop exit signals would show the same aspect. However I don't recall any such situation on the prototype - perhaps one of our experts can comment? I'm also wondering whether the second loop would have a trap at the exit to protect against shunting moves overrunning into the first loop.

 

Strange tho' it might sound but that is very much the situation I specified into a scheme back in the early '90s B) . But the way it was done - albeit with a longer distance between the convergence of the two loops and the mainline connections - was to provide signals at teh loop convergence and another where the mainline was joined; the distance between the two is well under braking distance but was acceptable as trains were starting away. But I think it would probably look odd on a model with much shorter distances.

 

BUT don't tie yourself up with fancy things like this - the only reason I did it was to allow for 120 slu trains and it also included using right hand running in the loops if a long train was to be accommodated; definitely not one out of the normal box of bits.

 

The small set of sidings I'd suggest would be on a ground frame with no signals. This would be released by the signalbox when shunting was required, and moves controlled by hand signals.

 

That is not a bad idea - exactly what happens at a number of locations but depending on peroiod of introduction etc I would go for a power worked ground frame, with switcvhes mounted on a weatherprofed pedestal, rather than a lever frame.

 

If there was no main line signal (for the same direction) in line with the loop signals then the loop signals would probably be approach lit. They would show no aspect at all unless either a route was set into that loop or the loop itself was occupied. This is to avoid the loop signal causing confusion to drivers on the main line. The loop approaching Inverkeithing from the Aberdour direction had this arrangement when taken over by Edinburgh power box around 1980 and it was common on other Scottish power signalling schemes of the time. It would be a good talking point for the layout when people say "your signal has gone out!".

 

 

Yes, no, or maybe. Approach lit signals are very much frowned upon nowadays - I would go for co-locating (or 'approximately co-locating') as it will look good and give you greater operational flexibility.

[beast66606]

Approach lit signals were used to stop "read through", I'm not sure the curves on the layout are "right" to justify approach lit signals and they need to be lit whenever a route is set towards them or if trains are in the loops so would be on a lot of the time anyway on the model !

 

I assume the box is a level crossing frame ? if the signals are EH controlled ?

 

Why not show us your proposed signalling and we can comment on it ? - best way to learn.

[sulzer27jd]

Approach lit signals were used to stop "read through", I'm not sure the curves on the layout are "right" to justify approach lit signals and they need to be lit whenever a route is set towards them or if trains are in the loops so would be on a lot of the time anyway on the model !

 

I assume the box is a level crossing frame ? if the signals are EH controlled ?

 

Why not show us your proposed signalling and we can comment on it ? - best way to learn.

 

This is what I have come up with by way of a signal diagram;

 

The junction at the left is the route to Thornton (not modelled)

 

The headshunt at the end of the loops is to protect the mainline only, it does not get used for shunting etc. Shunting is done in one direction on each main line. What I mean is the Up trains (left to right) shunt the top right yard [Dysart] and go off scene. The then return as a Down train and shunt the right bottom yard [balbeggie].

 

Any advice welcome. It would also be useful to see what the frame would look like for the two small yards.

 

Thanks again all.

 

John

[Edwin_m]

Approach lit signals are very much frowned upon nowadays - I would go for co-locating (or 'approximately co-locating') as it will look good and give you greater operational flexibility.

 

True, but they were quite common in the OP's area and period - I travelled daily from Fife to school in Edinburgh between 1978 and 1980 so I was pretty familiar with the resignalling. I don't remember seeing any outside Scotland though.

 

Re the signal diagram the loop exit signals should be three or four aspect not two aspect. I'd also stick with three aspects on the main line, as far as I recall there were no four-aspects in Fife.

[sulzer27jd]

 

Re the signal diagram the loop exit signals should be three or four aspect not two aspect. I'd also stick with three aspects on the main line, as far as I recall there were no four-aspects in Fife.

 

Noted - thanks

[beast66606]

Whats the 2-aspect in the bottom right for ?

 

Ground signals

[sulzer27jd]

Whats the 2-aspect in the bottom right for ?

 

Ground signals

 

The two aspect is the exit from a coal loading facility. Should this be a three as well?

[beast66606]

The two aspect is the exit from a coal loading facility. Should this be a three as well?

 

It should be three and moved back to be in rear ("on the approach to") of the facing points, it also needs a theatre.

 

When drawing signals its always clearer if you draw a stick post too - ground signals are very important in this type of layout, I would have a go at putting them in.

 

hth

[sulzer27jd]

Thanks all for the above info - here is what the signalling now looks like;

 

 

2 questions;

 

1) - the small yard top right (Dysart) - when this is being shunted it is necessary to put the whole train inside the yard in order to keep the mainline clear. Would this then require ground signals to carry out the entrance to and the exit from the yard?

 

2) - The yard at the end of Balbeggie Sidings (off the second loop), this would be treated as if a train is occupying the loop and manoeuvres into the yard itself would be hand signalled. What would this arrangement look like on the ground? Would there be a ground frame for the yard entrance? I am assuming that the selection of yard road would be by hand thrown turnouts but from what has been said previously the crossover giving access to the sidings would be locked to the signalbox. Any pictures would be very helpful.

 

Thanks again - John

[beast66606]

Unless the distance is great your signal on the loops to the right, with the right hand feather, would not be provided, the routing would be on the previous signals.

 

The yard on the loop would be connected by a ground frame, there are quite a few on the Edinburgh patch (I've been playing SimSig Edinburgh so I've come to know the area quite well !), do a google and see what you can find.

 

I would look at the signal spacing on the main lines, I think they will look too squashed up and you may need to lose a couple, remember real signals are typically *around* 2/3 mile apart.

[Edwin_m]

Unless the distance is great your signal on the loops to the right, with the right hand feather, would not be provided, the routing would be on the previous signals.

 

Looking at the scale plan in the original post, I think the signalling plan is a bit misleading in its proportions and these signals are in fact OK.

[Edwin_m]

1) - the small yard top right (Dysart) - when this is being shunted it is necessary to put the whole train inside the yard in order to keep the mainline clear. Would this then require ground signals to carry out the entrance to and the exit from the yard?

 

2) - The yard at the end of Balbeggie Sidings (off the second loop), this would be treated as if a train is occupying the loop and manoeuvres into the yard itself would be hand signalled. What would this arrangement look like on the ground? Would there be a ground frame for the yard entrance? I am assuming that the selection of yard road would be by hand thrown turnouts but from what has been said previously the crossover giving access to the sidings would be locked to the signalbox. Any pictures would be very helpful.

 

To answer the second one first, you are right the frame would control the access crossover and would be released by the signalbox. It would have to be restored to normal with the points normal before a train could be signalled into the loop. The ground frame would not control signals, unless the sight lines were too poor for hand signalling to be used. The frame is either two (in this case I think) levers or a small panel. It is located where the shunter can see the points and give hand signals to drivers, and is normally open to the elements. The other points would be hand worked by levers alongside them.

 

On the first one you can use exactly the same ground frame arrangement for Dysart with no shunt signals needed. The ground frame could be locked normal while trains continued to shunt over the hand-worked points within the yard. If you need signals, then if the headshunt is actually used for shunting you need either an extra shunt signal or a yellow shunt signal - not sure which they did at Edinburgh or even if anywhere on the panel needed it.