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Bracket with one home arm and one distant arm

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Bracket with one home arm and one distant arm

Unread postby Danny252 » Thu Feb 25, 2016 9:59 am

In a recent discussion with an interested amateur, I pointed out that a bracket with a home arm on the main post and a distant arm on the second post wouldn't be prototypical.

However, it has since occurred to me that in signalling, there is always an exception to the rule! Can anyone say if and where such an example existed in this case? I imagine it would be a location that had severe limitations in either sighting or in available space.

To give a visual example, the lower arm on this bracket would be a distant arm in the envisaged scenario.
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Re: Bracket with one home arm and one distant arm

Unread postby Pete2320 » Thu Feb 25, 2016 12:12 pm

A scenario like this could possibly occur if the two arms applied to different lines, say a multiple track line or perhaps a diverging junction.
Would this thread perhaps be better placed in "Historical"?

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Re: Bracket with one home arm and one distant arm

Unread postby Danny252 » Thu Feb 25, 2016 1:47 pm

Pete2320 wrote:Would this thread perhaps be better placed in "Historical"?


I was in two minds about it, as it's more or less asking for a bit of trivia. I wouldn't object to the thread being moved if it were deemed sufficiently serious!
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Re: Bracket with one home arm and one distant arm

Unread postby StevieG » Thu Feb 25, 2016 3:19 pm

Pete2320 wrote:A scenario like this could possibly occur if the two arms applied to different lines, say a multiple track line or perhaps a diverging junction.
Would this thread perhaps be better placed in "Historical"?

Pete
In the early-mid '60s, a signal to demonstrate Pete's first point could be seen on the ex-GNR main line near Hornsey station, where there was a 2-dolled right-hand bracket signal with equal-height arms - stop arm on the left, distant on the right - as close to each other horizontally as would befit a normal 'splitting' signal.
The arms however applied to two parallel same-direction Goods running lines (therefore, low speed), and were worked by different boxes.

I think the configuration resulted from changes to the outlet connections with the Up Goods lines from, and layout of, Ferme Park Up yard, either following abolition of the nearby Ferme Park North Up Box, or perhaps subsequently.
The stop arm was the Up Goods No.2 line First Home for Ferme Park South Up (FPSU); the distant was that for the Up Goods No.1 for Harringay Up Goods Box (on which line FPSU was not a block post).
Then circa 1968-70 things changed again and Ferme Park S.U. and its connections with the UG2 line were also abolished : The UG2 line stop arm on the said signal structure was then replaced by a second distant arm alongside the first, still for UG2, as that line's Distant for HUG Box.
BZOH

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Re: Bracket with one home arm and one distant arm

Unread postby andrewnummelin » Mon Oct 24, 2016 7:03 pm

Only just came across this thread...

I have a copy of a signalling diagram submitted to the Board of Trade which shows a bracket signal with a central main post with a stop arm and on both sides of it a doll with a distant.
It doesn't seem possible to add an attachment to this post so I've put a scan of part of the diagram up onto my web site.
http://www.andrew.nummelin.me.uk/ADR/Glyntaff/MT6-1732-4%2057part.jpg
The signal is in the top right of the diagram, and I presume the distants refer to junctions that are off the bottom left.
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Re: Bracket with one home arm and one distant arm

Unread postby Chris Osment » Tue Oct 25, 2016 12:09 pm

andrewnummelin wrote:I have a copy of a signalling diagram submitted to the Board of Trade which shows a bracket signal with a central main post with a stop arm and on both sides of it a doll with a distant.

Although I have never found a supporting photo, there is diagram and Signal Instruction evidence that a similar arrangement existed at Evercreech Junction prior to 1904. The South box Up Starting had dolls either side which carried the Up Main and Up Branch Distants for the North box.
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Re: Bracket with one home arm and one distant arm

Unread postby Mike Hodgson » Tue Oct 25, 2016 1:03 pm

I don't think I've seen anything in any rule book descriptions of signals that say it's incorrect. I think it just looks odd to us because we are so accustomed to the more usual arrangement, which must be cheaper because of its greater simplicity. Economy rules.
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Re: Bracket with one home arm and one distant arm

Unread postby S&TEngineer » Tue Oct 25, 2016 3:58 pm

Well it was certainly permitted on the WR in the late 1950s. Extract from WR Technical Instruction A13; Sighting of Semaphore Signals (Use of Standard Structures) - Ref Section 12, 3rd Paragraph:

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Re: Bracket with one home arm and one distant arm

Unread postby StevieG » Fri Nov 18, 2016 1:25 pm

andrewnummelin wrote:I have a copy of a signalling diagram submitted to the Board of Trade which shows a bracket signal with a central main post with a stop arm and on both sides of it a doll with a distant.
Costs apart, merely a way of combining splitting distants with a rear stop signal, where the lines 'splitting' were perhaps regarded as of equal status, and so putting neither distant below the stop arm avoided conferring a suggested status of greater importance to either route which the company / signal engineer / operating department did not want to do ?
BZOH

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Re: Bracket with one home arm and one distant arm

Unread postby andrewnummelin » Fri Nov 18, 2016 7:32 pm

StevieG wrote:
andrewnummelin wrote:I have a copy of a signalling diagram submitted to the Board of Trade which shows a bracket signal with a central main post with a stop arm and on both sides of it a doll with a distant.
Costs apart, merely a way of combining splitting distants with a rear stop signal, where the lines 'splitting' were perhaps regarded as of equal status, and so putting neither distant below the stop arm avoided conferring a suggested status of greater importance to either route which the company / signal engineer / operating department did not want to do ?


That makes sense: I don't have the detailed track layout with me, but the two distants probably referred to the up direction junction at Pontypridd for the Rhondda and Merthyr lines. The signal mentioned was on the ADR line from Caerphilly being, I believe, the home signal for the Interchange Sidings West box at the up end of the loop sidings. This was followed by a stop signal protecting the junction between the ADR and TVR: I think this signal must have had a dual function of being the home signal for the junction box and the starting signal for the Interchange Sidings box. A fascinating area with a halt with a platform only on the up line for terminating trains (through trains didn't stop): at one time the down trains starting from the halt had to run around 1/4 mile wrong line before crossing to the down line... and a lovely array of signals controlling the entrance to the interchange siding loops.
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