Signals and Norton Fitzwarren (2nd Attempt)

This might be a duplicate because the BT Internet news servers are not quite up to the task apparently!

I'm just putting together a signal box design in SSI

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for Norton Fitzwarren junction just west of Taunton. I have some questions:

1) What is an Adv. Starter for? does it copy another starter or is it operated independently?

2) What are the spring points on the diagram I found it the GWR Historical Layouts book? They look like catch points but they are labelled, whereas the other catch points on the diagram are not.

And also a request,

If anyone has any photos/diagrams/etc of Norton Fitzwarren junction but particularly information relating to the signal box both physically and operationally, I would be happy to pay for any postage or even better if it is on the web or in books that I could get from the library. The diagram I have is abridged and only contains a few signal numbers and does not number the points. I would like to label them correctly both for accuracy and also to help me with my SSI layout.

Thanks

Luke Briner

Reply to
Luke Briner
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Where there is an Advanced Starter it will be the block signal and hence require 'Line clear' from the next box before it can be pulled off. Its purpose is to allow a train to pull forward out of the station, past the Starter, when the block is not clear. This may be to deal with congestion or, more likely, to allow for shunting moves.

I don't know thae particular layout but its usual to label spring points as such as the operating rules relating to those are different from the others which will be worked by levers in the box.

Note that there are 'Catch points' and 'Trap points' which look the same but serve didfferent purposes, the first are normally sprung whilst the second are usually worked by box levers often as part of a crossover. Catch points are to catch any vehicles which break away from the back of a train going uphill and are usually located just outside the starter or advanced starter on the running line so that a break away vehicle will be derailed before it runs back into a train standing at the signal. Trap points are to prevent any unsignalled movement onto the main line from goods lines or sidings and are located at all locations where such lines join the main line.

Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Reply to
Keith Norgrove

"Keith Norgrove" <

I thought an Advanced Started was required when there were/are any points, such as a crossover, bay exit, siding exit etc., past the Starter. This is to enable movement through or over these points past the starter when the next block is not clear.

AIUI, the Advanced Starter can also be used to hold trains and clear the platform, before the "Line Clear" has been given by the next block, so that a following train can draw forward into the platform.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

Thanks Keith,

Are you saying that the spring points and catch points are 'automatic' and that they allow travel in one direction but derail in the opposite? I always assumed that catch points were coupled to the signal protecting the exit of a siding and that the points were in reverse position whenever the signal was at danger.

Looking at the diagram I have, it looks like the spring points (maybe they are catch points?) protect the junction from trains that should have left it as you suggested. They are placed on the down goods and two of the down branches on the down side of the junction. The down main is not protected but would not conflict with any other route across the junction.

Luke

Reply to
Luke Briner

Exactly what I said above, ie shunting moves.

And what I said above as pulling forwaard to deal with congestion. Seems we agree Roger. Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Reply to
Keith Norgrove

Essentially yes, if a train needs to set back over such spring catch points there was usually a hand lever that would have to be held over against the spring for the entire movement.

Those protecting the exit of a siding are known as trap points, the normal position is the derailing position, the point would have to be reversed before the exit signal could be cleared. Hence they would be operated from the lever frame with locking " exit signal released by trap points reverse"

Sound like catch points but difficult to give a positive answer as I have no idea what the layout was at Norton Fitzwarren.

Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Reply to
Keith Norgrove

"Luke Briner

As the previous poster pointed out, "Catch" points and "Trap" points are two entirely different beasts.

"Catch" points, as their name implies, are/were there to catch vehicle running away wrong line. They are, or were, usually located on or at the bottom of steepish grades are/were designed to "Catch" unbraked goods trucks that had broken away from a goods train and derail them into the line side. "Catch" points are full automatic as they are sprung in the derail position. However, they usually can/could be aligned for the through route and locked in place. This was required in case of wrong road running or if a train had to set back and in so doing, would derail the last vehicles.

Trap points are interlocked and are either operated from their own interlocked lever in the signalbox or operate in unison with running line points.

Do not confuse trap points with catch points, they are not the same thing.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

"Keith Norgrove"

We do indeed Keith. My addition was there because you implied there were points after the starter but you didn't actually say so. I think. :-)

It amazing how many modellers haven't a clue about signalling and correct track layout, especially these days when they try to model the steam era. I think many of them who weren't there model what they see today and assume it's always been like that.

Even so called "heritage" railways build track layouts that wouldn't have been acceptable in the steam era.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

Acceptance of trains - giving the line clear - is NOT related to the presence or otherwise of an advance starter, it is down to block regulations which dictate, for example, 440yds in front of the home - this being the first stop signal. An advance starter *may* mean the train can pull forward and therefore provide the 440 yds in front of the home but this is by no means definite.

HTH

Reply to
David Skipsey

Yes, I knew that, but was using the KISS principle in the explanation.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

You are confusing Line clear release of the Advance Starter (or Starter) in the original message with clearing the overlap to give Line clear to the box in rear, for this latter purpose it was usual to add an Outer Home rather than an Advanced Starter. Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Reply to
Keith Norgrove

"Keith Norgrove"

Look to Barnham, at least in "steam" days and maybe now.

The "up" line, I think it is, the one going to Brighton, had an outer home, inner home, starter and advanced starter. Trains were frequently divided and united at Barnham, still probably are, so this signal arrangement came in real handy.

-- Cheers Roger T.

Home of the Great Eastern Railway

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Reply to
Roger T.

On semaphore signaled areas a signal box could have the following arrangement, from the approaching drivers point of view.

1) Distant only off when all home and starter signals are off 2) Outer home (optional) used at particularly busy areas or where there are a lot of junctions to sidings or other running lines. 3) Inner home (known as home when there is no outer home) 4) Starter when there is no advanced starter this controls entry to the next block section 5) Advanced starter (optional) where present this in particularly busy areas or where there are a lot of junctions to sidings or other running lines.

Where signal boxes are close together starters/advanced starters may also have slotted distants to the next signal box, distant can only clear when the starter signal is off.

Probably near the entrance to loops so that any breakaways from unfitted freights will not run onto the running line.

Catch points are normally found on plain line to catch any breakaways from unfitted freights.

Taunton is currently controlled from Exeter PSB which has Western Region free wired relay interlocking, pre SSI. With non-swinging overlaps for students of power siganaling.

Reply to
Chris

Barnham is now colour light controlled since the late 1980's. There were probably advanced starters to allow trains to run around as there was and still is trailing crossover at the Brighton end of the station and the same was true for the Portsmouth end.

Chris

Reply to
Chris

I don't know about this location, but spring points were used at some junctions as an automatic routing device. Presumably this saved the cost of point control rodding, etc. I think there used to be some at the junction for the former Horsted Keynes line north of Haywards Heath. If I recall correctly, they were normally set for southbound trains on the main line. However, when a train was running (slowly) off the branch line towards Haywards Heath, each set of wheels pushed the points so that they were aligned for the branch. When the train had passed, the spring pushed the points back so that they were set for main line trains. Obviously, the strength of the spring must have been designed to maintain safe operation without derailing trains.

Bevan

Reply to
Bevan Price

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