Ambergate Signalling Question

[RichmondCommu]

Hi everyone,

Apologies if this is a stupid question but I'm just a woman who likes trains!

As you leave Ambergate station for Matlock there is a signal on the left hand side but I'm not sure why given that the branch is protected by the use of a token. In that case as soon as a train has entered the branch surely another train cannot do the same?

Any information would be gratefully received.

Many thanks,

Angela

 

[MarkyT]

A numbering plan from Simsig is here: https://www.simsig.co.uk/Media/Wiki//simulations/derby/derby_2000-2005_signal_number_plan.pdf

This shows the layout at Ambergate with down signal 572 on the branch as you say. It is this signal that is released by withdrawal of the token on the platform. A train from Derby could turn back at Ambergate station without withdrawing a token, but once obtained no further trains can be admitted to the platform from the main line to 572 as there is no up signal protecting the platform.

 

[Legolash2o]

Looking at the signal diagrams the signal is "572" and it doesn't look like there's any signal at all beyond that. The signal block associated with 572 looks around 500m and looks like there is no signal block beyond that all the way to Matlock.

There is a signal "R571" on the right hand side but it just repeats a signal near Ambergate South Jn.

Someone with more experience than myself will know a definite answer though.

 

[Tomnick]

Trains towards Matlock aren't in possession of the token when they leave the main line and enter the platform at Ambergate (the only practical location for the token instrument is on the platform), so that portion of line can't be considered part of the token section. DY572 then controls entrance to the token section, once the token has been withdrawn - although, as MarkyT notes, the lack of a protecting signal in the Up direction means that a second train can't be allowed to enter the platform (to turn back or otherwise) whilst there's a token out.

 

[MarkyT]

Looking at the signal diagrams the signal is "572" and it doesn't look like there's any signal at all beyond that. The signal block associated with 572 looks around 500m and looks like there is no signal block beyond that all the way to Matlock.

There is a signal "R571" on the right hand side but it just repeats a signal near Ambergate South Jn.

Someone with more experience than myself will know a definite answer though.

You can get into Ambergate station from Derby without the token but you can't go beyond 572 until one is withdrawn. The machine is on the platform, so trains need to call in both directions to obtain and give up a token. Once a token has been withdrawn no further down train can be signalled from the south into the platform.

 

[Kneedown]

Just to add to previous answers, there is a token machine at Matlock also, so a train can withdraw a token at Ambergate, proceed to Matlock, shunt into the sidings and put the token in the machine there which will enable another train to be signalled onto the branch at Ambergate.
This scenario was used the other week. Railhead treatment train goes to Matlock, sits in sidings to allow passenger service onto branch. When return passenger clears Ambergate the RHTT leaves Matlock sidings for return working.

 

[John Webb]

Presumably the token machine at Matlock is also needed when a train is passed onto or is to return from the Peak Rail line.

 

[Tomnick]

Presumably the token machine at Matlock is also needed when a train is passed onto or is to return from the Peak Rail line.

Yes, anything being 'shut inside' beyond the end of the token section will have to restore the token to the instrument (to free up the single line) and obtain a token before coming back out. I don't know whether Derby's just got one release that's good for both instruments, though presumably there's a control to prevent a token being obtained at Matlock if there's a train in (or signalled into) the platform at Ambergate.

 

[MarkyT]

Presumably the token machine at Matlock is also needed when a train is passed onto or is to return from the Peak Rail line.

Correct, they use the same ground frame to access Peak Rail via the NR sidings.
There must be some special controls to prevent a token being released from the Matlock instrument when a route is set into Ambergate platform from the south or any of the track circuits in the route towards DY572 remain occupied.