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Special switch at Elsenham

British signalling of the past (UK, excepting Northern Ireland)

Re: Special switch at Elsenham

Unread postby ge.signals » Fri Nov 3, 2017 3:26 pm

Re stopping freight trains at New Hall Up Auto: I suspect that there may have been a misunderstanding about this. I was told that this only happened when Stansted was switched out and Up trains could take a long time to clear the long Elsenham - Bishop's Stortford section. With a slow loose-coupled train approaching on the Up Line, if Elsenham was still awaiting 'Train Out' from Bishop's Stortford, the slow loose-coupled train would have to be stopped at Elesnham's Up Starter which would in turn require the loose-coupled train to be brought almost to a halt at Elesnham's Up Home before being brought forward to the Starter to await 'Train Out' from Bishop's Stortford and then 'Line Clear'. This could cause wagons in the loose-coupled train to surge backwards and forwards as it slowed and then moved forward, and with two sets of catch-points on the approach to Elesnham's Up Home, it was deemed prudent to hold the train at the New Hall Up IB signal by using the 'Emergency' switch until the previous train had cleared the section ahead.

This is what I was told by someone who was a frequent visitor to Elsenham box who knew Elsenham well.

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Re: Special switch at Elsenham

Unread postby Richard Pike » Fri Nov 3, 2017 5:47 pm

Regarding the switch do you know what it felt like to move it? Did it stay put or was it spring loaded?
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Re: Special switch at Elsenham

Unread postby Danny252 » Fri Nov 3, 2017 7:28 pm

ge.signals wrote:This could cause wagons in the loose-coupled train to surge backwards and forwards as it slowed and then moved forward, and with two sets of catch-points on the approach to Elesnham's Up Home, it was deemed prudent to hold the train at the New Hall Up IB signal by using the 'Emergency' switch until the previous train had cleared the section ahead.


John's point, partially backed up by the only diagram I can find online (link), is that there were plenty of catch points in the vicinity of the New Hall Up IB signal - in its overlap (presumably removed in the linked diagram), and between the IB signal and its distant - but apparently none near the Up Home (although again, the diagram I linked shows evidence of alteration there).

Therefore, if a freight is being slowed/stopped at the IB Home, the same concerns about "surging" in the vicinity of catch points apply.
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Re: Special switch at Elsenham

Unread postby ge.signals » Fri Nov 3, 2017 7:59 pm

Richard Pike wrote:Regarding the switch do you know what it felt like to move it? Did it stay put or was it spring loaded?


Unfortunately I never saw it or used it - just relaying info passed on to me by those who knew Elsenham before closure. However, the photo seems to show the handle staying put. I find myself wondering why an old telegraph instrument and not a simple switch?

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Re: Special switch at Elsenham

Unread postby ge.signals » Fri Nov 3, 2017 8:19 pm

Danny252 wrote:
ge.signals wrote:This could cause wagons in the loose-coupled train to surge backwards and forwards as it slowed and then moved forward, and with two sets of catch-points on the approach to Elesnham's Up Home, it was deemed prudent to hold the train at the New Hall Up IB signal by using the 'Emergency' switch until the previous train had cleared the section ahead.


John's point, partially backed up by the only diagram I can find online (link), is that there were plenty of catch points in the vicinity of the New Hall Up IB signal - in its overlap (presumably removed in the linked diagram), and between the IB signal and its distant - but apparently none near the Up Home (although again, the diagram I linked shows evidence of alteration there).

Therefore, if a freight is being slowed/stopped at the IB Home, the same concerns about "surging" in the vicinity of catch points apply.


Must find a gradient diagram for the Elsenham area but as I have stated previously, I am only relaying info passed on to me by people who have worked Elsenham before it closed.

By the way, your link to the diagram is actually my original diagram superbly digitally repaired and restored by Owen Stratford.

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