Why does this signal need a warning sign?

[htwestern]

At Bedminster station, on the track that goes through platform 3 towards Temple Meads, there’s a set of signs warning about the distance to signal BL2166. There’s one at an oddly specific ‘587 metres’ and one around ~300m IIRC.

What’s special about this signal that it needs a warning sign? Isn’t signal placement in the route knowledge of drivers?

 

[zwk500]

Is the signal perhaps not visible until quite late to the driver? There are similar signal warning signs at Luton Airport Parkway I think.

 

[800301]

At Bedminster station, on the track that goes through platform 3 towards Temple Meads, there’s a set of signs warning about the distance to signal BL2166. There’s one at an oddly specific ‘587 metres’ and one around ~300m IIRC.

What’s special about this signal that it needs a warning sign? Isn’t signal placement in the route knowledge of drivers?

BL2166 is a Multi-SPAD signal and therefore signs have been placed to heighten awareness of this signal

 

[rower40]

The previous signals (BL2172 on Up Relief, BL2174 on Up Main) are before the station, and BL2166 may not be visible from the station. It's possible that a driver, distracted by performing the station stop, could need a prompt to recall what the previous signal's aspect was - i.e. if it was yellow, to be ready to start from the station, and then stop again at BL2166.

 

[The exile]

At Bedminster station, on the track that goes through platform 3 towards Temple Meads, there’s a set of signs warning about the distance to signal BL2166. There’s one at an oddly specific ‘587 metres’

Presumably the sign is positioned where drivers stopped at the stop point will see it, and the distance has to be accurate (at least to the metre). Either that or 587 metres is 600 yards…

 

[Undiscovered]

It's there as a reminder, for stopping trains, that the next signal is particularly close, and mitigates against the driver taking full power, as his previous aspect may have been green, and then sighting the signal, only to find it's gone to red/blank due to a signalling fault, and subsequently passing it at danger.

 

[edwin_m]

It's there as a reminder, for stopping trains, that the next signal is particularly close, and mitigates against the driver taking full power, as his previous aspect may have been green, and then sighting the signal, only to find it's gone to red/blank due to a signalling fault, and subsequently passing it at danger.

Any signal could revert due to a fault, or in may cases emergency cancellation/replacement, and the driver wouldn't be held to blame if they couldn't stop on seeing it. The warning is more likely because of the SPAD risk mentioned above, that the driver passes the previous signal at single yellow and is distracted by the station stop. I assume the distance to accelerate before the signal comes into sight is enough to reach a speed it's not possible to stop from in the remaining distance.

 

[MadMac]

The previous signals (BL2172 on Up Relief, BL2174 on Up Main) are before the station, and BL2166 may not be visible from the station. It's possible that a driver, distracted by performing the station stop, could need a prompt to recall what the previous signal's aspect was - i.e. if it was yellow, to be ready to start from the station, and then stop again at BL2166.

There was at least one place with a station stop that used a “What was the last signal?” sign as a prompt.

 

[John Webb]

Couldn't they site a repeater signal within sight of the platform so the driver knows what is happening ahead?

 

[craigybagel]

There was at least one place with a station stop that used a “What was the last signal?” sign as a prompt.

Wrexham General has a warning sign reminding drivers to check the AWS sunflower departing the station, as the next signal isn't visible around a curve and as it protects a single track section it can often be at danger.

An admirable idea - but between the previous signal and the station there's a permanent AWS magnet for a speed reduction at the same place as the signal (70 to 30) - so even if the previous signal was green the AWS sunflower will still always be on!

 

[800301]

Couldn't they site a repeater signal within sight of the platform so the driver knows what is happening ahead?

That would cost money…

While I don’t know the exact signal and sighting (which has now been described in the post below) these signs are normally put in places where a Banner Repeater would have little to no use, normally approaching high risk junction signals, on the routes I drive, the ones I can think of off the top of my head the signal is in clear view but there is a higher than normal risk associated with that signal such as junction speed or shorter than normal signal section, or other signals that could be a distraction, there are also locations where we have countdown markers up to signals as they again are high risk and are or have been multi SPAD signals, all about covering risk as much as possible, take Reading for example, only recently after a few SPAD’s in a short space of time did they decide it might be helpful to put the platform numbers on the closing up signals they relate too so that it’s even easier to identify your signal

 

[Annetts key]

BL2166 is a Multi-SPAD signal and therefore signs have been placed to heighten awareness of this signal

Is the correct answer. However, it's the history of the signal rather than the current name that matters. As this was B25 when controlled by Bristol Panel.

B25 (which is for the Up Relief line) was originally mounted on a bracket along with B27 (for the Up Main). But a a SPAD occurred at one of these (I forget all the details, this was years ago), the driver allegedly got confused as to which signal applied to which line.

As a result, a number of changes were made. Reminder signs (like in the OPs photo) were provided for both signals (plus some others in the same area). Plus B25 (now BL2166) was moved from on top of the bracket and repositioned on the "post" of the bracket (lower in height).

== Doublepost prevention - post automatically merged: 11 Aug 2025 ==

The previous signals (BL2172 on Up Relief, BL2174 on Up Main) are before the station, and BL2166 may not be visible from the station. It's possible that a driver, distracted by performing the station stop, could need a prompt to recall what the previous signal's aspect was - i.e. if it was yellow, to be ready to start from the station, and then stop again at BL2166.

The only reason that BL2166 may not be visible from the station, is the vegetation. When the vegetation is cut back, BL2166 can be seen from the station.

 

[PG]

When the vegetation is cut back, BL2166 can be seen from the station.

Interesting!! Presumably this vegetation is on NR owned land? One would think with BL2166 being a Multi-SPAD signal that, as well as the warning sign, cutting back the vegetation would be a sensible risk reduction measure...

 

[Jimini]

take Reading for example, only recently after a few SPAD’s in a short space of time did they decide it might be helpful to put the platform numbers on the closing up signals they relate too so that it’s even easier to identify your signal

I know I'm going waaaaay back here, but I always remember seeing the chevron countdown markers to (I assume) the final approach signal on the DM on approach to the old P4 before Reading got its significant facelift.

(Yes, this was back in HST days, and no, I wasn't hanging out of the droplight window like a dog!)

 

[Annetts key]

Interesting!! Presumably this vegetation is on NR owned land? One would think with BL2166 being a Multi-SPAD signal that, as well as the warning sign, cutting back the vegetation would be a sensible risk reduction measure...

The official sighting distance is just less than the location on the platform from where the guard/train manager/conductor can see the signal. I can't say how badly the vegetation affects what the driver can see.

And yes, the vegetation is all on Network Rail land.

Here's a diagram:

(picture is a diagram showing the relative positions of the reminder sign, the station and the signal - the items in red are the "new" signalling names/numbers/details, the items in green are the old signalling names/numbers/details, all distances are in metres).

Notice that the reminder sign for the signal is BEFORE the train gets to the platform.

== Doublepost prevention - post automatically merged: 12 Aug 2025 ==

Okay, this is an old video (three years old now) and the train it was filmed on was going in the down (away from Bristol) direction. But it does show the up platforms (2 and 3) and gives you an idea of the amount of vegetation.

 

[PG]

@Annetts key thanks for your most informative posts, much appreciated.

 

[MadMac]

For those interested in SPAD mitigation, This report provides some good insight.

 

[Thames99]

I know I'm going waaaaay back here, but I always remember seeing the chevron countdown markers to (I assume) the final approach signal on the DM on approach to the old P4 before Reading got its significant facelift.

(Yes, this was back in HST days, and no, I wasn't hanging out of the droplight window like a dog!)

Could this be related to slip coaches that some down trains had for Reading? These markers would have helped the guard/ driver to release and brake it at the correct distance from the platform.