Im confused...

A distant signal is one that cannot display a 'danger' aspect. It is however able to display a 'caution' aspect, which gives the driver advance warning that the stop signal ahead may be displaying 'danger'. The distant signal is installed roughly at full braking distance on approach to the stop signal to which it applies, taking into account the gradient, the permitted speed, and the braking performance of trains. On sighting a 'caution' aspect, the driver must prepare to stop at the signal ahead. If the distant signal shows a 'clear' aspect, the train may maintain full speed. A single signal may be equipped to function both as a stop signal and a distant signal.

Probably a distant signal.


Wickipedia said:

A distant signal is one that cannot display a 'danger' aspect. It is however able to display a 'caution' aspect, which gives the driver advance warning that the stop signal ahead may be displaying 'danger'. The distant signal is installed roughly at full braking distance on approach to the stop signal to which it applies, taking into account the gradient, the permitted speed, and the braking performance of trains. On sighting a 'caution' aspect, the driver must prepare to stop at the signal ahead. If the distant signal shows a 'clear' aspect, the train may maintain full speed. A single signal may be equipped to function both as a stop signal and a distant signal.

So presumably, the signal preceeding the distant signal would show a danger aspect, ignoring the distant signal aspect?

If its color lights then it's likely a repeater not a distant (which is a name from the semaphore days and means something completely different).

I suspect the vast majority, if not 100%, of distant signals on Network Rail that are on their own post are colour light signals.

Also I would be interested to know, for what reason would this type of repeater signal be used over and above a banner repeater?

• to indicate to the driver whether he/she can enter the following block section


• to indicate the state of the next signal to the driver, so he/she can brake in time

When approaching a stop signal at line speed, drivers have to be able to see it properly for a certain amount of time before passing it.

I drove past this signal today and did my best to get a look at the identifier plate below the lamps.

It read:
MP
5** (Cant remember exact number)
R
^

Well, technically that would apply even to repeaters!

R signals cannot show red, as the driver would have to stop at it.

D1001R on Dundee panel. I remember many years ago, just after it was installed, experimenting with night photography to see if I could photograph it with all 3 aspects displaying (it was handily placed to do that). I seem to recall noticing years later the Y blanked and I think the head may have been changed since to a 2A but I'd need to check that.

There was also one route which did have repeater signals which did have a red aspect, although I don't know if they had R plates - they're not there in real life any more but they are in a SimSig sim.

" said:

Also I would be interested to know, for what reason would this type of repeater signal be used over and above a banner repeater?

Basically main signals have two functions:

• to indicate to the driver whether he/she can enter the following block section


• to indicate the state of the next signal to the driver, so he/she can brake in time

If the signal spacing is approximately equivalent to the maximum required braking distance, both functions can be combined into one signal and you'll get classic three aspect signalling.
If you decrease the signal spacing even further, you move over to four aspect signalling, where the full braking distance is provided via the Double Yellow - Yellow - Red sequence of aspects.

If on the other hand you increase the distance between consecutive stop signals (mostly because you don't need the full capacity provided by three/four aspect signalling and want to save some money), you reach a point where providing a combined signal for those two functions no longer makes sense - if you've got a five mile long block section, it doesn't make sense to show a yellow aspect to the driver just because the next signal five miles away is displaying a red. Therefore, separate signals are provided in the form of stop signals (red/green) and repeaters (yellow/green).

Banner repeaters have a different purpose. When approaching a stop signal at line speed, drivers have to be able to see it properly for a certain amount of time before passing it. Where that is not possible due to the curvature of the line, bridges or anything else obstructing the view of the signal, banner repeaters are provided.

You can't have a Green Signal reading directly onto a red signal in the UK so in 2 aspect signalling areas you have a repeater to stop this from happening (it's either Y onto G or G onto G).

" said:

You can't have a Green Signal reading directly onto a red signal in the UK so in 2 aspect signalling areas you have a repeater to stop this from happening (it's either Y onto G or G onto G).

You can in a semaphore area, you'd have a R/Y distant, reading to a R/G home reading to a R/G starter.

" said:

" said:

You can't have a Green Signal reading directly onto a red signal in the UK so in 2 aspect signalling areas you have a repeater to stop this from happening (it's either Y onto G or G onto G).

You can in a semaphore area, you'd have a R/Y distant, reading to a R/G home reading to a R/G starter.

However, the driver will not see the aspect sequence G->R, due to what was Rule 39a, which effectively gives a caution aspect. If a driver receives G onto R, he would be well within his rights to complain loudly.

Except if there's an exemption in the Sectional Appendix, which the driver would be expected to know before he's allowed to drive that route.

You can't have a Green Signal reading directly onto a red signal in the UK so in 2 aspect signalling areas you have a repeater to stop this from happening (it's either Y onto G or G onto G).