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Difference between banner repeaters and co-acting signals?

Ditop23

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Hi
What's the correct difference between banner repeaters and co-acting signals.

In the rule book.
It says BR are provided on approach to a signal when there is restrictive sighting of the signal. Tunnels bridges etc.

It says CS are provided to give both short and long distance sighting of the signal. It doesn't say why.

Any advice of the differences and whether they are interchangeable?


Thanks
 
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Mojo

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Co-acting signals would be provided alongside a signal, for example at a platform or by a bridge where the layout of the cab or other such infrastructure would ordinarily prevent the “main” signal being seen clearly.

A banner repeater would be some distance before the signal because the signal is not visible from that far away.
 

driver9000

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A Co-Acting signal shows the exact aspect the main head is displaying and are used at locations where the sighting of the signal is obscured ( next to each other platform 14 Manchester Piccadilly, platform 4 and Up Main where Co-Acting head is on the floor at Lancaster for example). A Banner repeater is provided a certain distance in rear of the signal where sighting time might not be met and shows whether the signal On (red) or Off (proceed) plus certain banners can show a green background when the signal is also green.
 
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43066

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Co actors can be adjacent to the main aspect but turned 90 degrees to it (eg Waterloo East, down slow), or can resemble main aspects (eg one at East Midlands Parkway on the up fast platform facing in the up direction, intended for trains approaching on the down fast, and mirroring the signal at country end of the down fast platform which is obscured by the curve)

Absolutely not interchangeable: as banners can be passed when “on”, co-actors generally can’t as they’re located right next to the signal they’re repeating, so this would result in a SPAD. As above many banners only show off or on, newer three state ones can show off, on and off (green).
 
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Co actors can be adjacent to the main aspect but turned 90 degrees to it (eg Waterloo East, down slow), or can resemble main aspects (eg one at East Midlands Parkway on the up fast platform facing in the up direction, intended for trains approaching on the down fast, and mirroring the signal at country end of the down fast platform which is obscured by the curve)

Absolutely not interchangeable: as banners can be passed when “on”, co-actors generally can’t as they’re located right next to the signal they’re repeating, so this would result in a SPAD. As above many banners only show off or on, newer three state ones can show off, on and off (green).

I'm trying to understand what's going on in the "turned 90 degrees" case : is this simply a situation where the train has to stop more or less alongside the signal, so much so that the main aspect can't be seen?
 

43066

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I'm trying to understand what's going on in the "turned 90 degrees" case : is this simply a situation where the train has to stop more or less alongside the signal, so much so that the main aspect can't be seen?

That’s exactly it. Too close to the main signal to read it, but the driver can see the co-actor through the side window.
 

zwk500

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I'm trying to understand what's going on in the "turned 90 degrees" case : is this simply a situation where the train has to stop more or less alongside the signal, so much so that the main aspect can't be seen?
Essentially, yes. See https://www.railsigns.uk/photos/p_clsig2.html#pic_mcus for an example at Penzance. I believe there's also 1 (some?) at Waterloo. As you can gather, a typical use case is at termini when the distance between the stopping point for arriving trains and the departure signal back out the other way is very similar to the length of the train itself.
 
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Sheridan

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Essentially, yes. See https://www.railsigns.uk/photos/p_clsig2.html#pic_mcus for an example at Penzance. I believe there's also 1 (some?) at Waterloo. As you can gather, a typical use case is when the distance between the stopping point for arriving trains and the departure signal is very similar to the length of the train itself.

Presumably your last sentence is referring to a platform where trains change direction?
 

edwin_m

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Platform at Nottingham also has a rotated co-actor. I can't help thinking such a big lamp right outside the side window will dazzle the driver.
 

Snow1964

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I'm trying to understand what's going on in the "turned 90 degrees" case : is this simply a situation where the train has to stop more or less alongside the signal, so much so that the main aspect can't be seen?
The first examples were on Southern Railway where bridges meant platform length was tight, and train had to stop almost level with the signal. Small repeater bulbs were mounted on the side so they could be seen from side window of cab.

Because these early bulbs stuck out the side of the signal post, they were affectionately known as pigs ears. (Not to be confused with 5 white divergence indicators which also stick out from main signal head). Nowadays the repeaters are separate light head, which may or may not be mounted on same structure.
 

FR510

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That’s exactly it. Too close to the main signal to read it, but the driver can see the co-actor through the side window.
I believe the co-actor was put in to accommodate 12 car formations at Waterloo East on the up slow. The platform is tight for 12 cars and the 12 car DOO monitors are very close to the starting signal. Placing the co-actor at 90 degrees next to the monitors enables the driver to study the monitors and check the signal aspect easily before proceeding with his despatch process.

When the maximum DOO train length was 10 cars the appropriate DOO monitors were/are a couple of coach lengths further down, which meant the starting signal was in clear view out the front windscreen.
 

Kilopylae

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Oxford and Devon
Hi
What's the correct difference between banner repeaters and co-acting signals.
Railsigns.uk explains this very clearly and succinctly: "Duplicate signals installed at the same longitudinal position are termed 'co-acting' signals, whereas an additional signal provided at a different longitudinal position from the signal it repeats is known as a 'repeater' signal."
 

Annetts key

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West is best
Hi
What's the correct difference between banner repeaters and co-acting signals.

In the rule book.
It says BR are provided on approach to a signal when there is restrictive sighting of the signal. Tunnels bridges etc.

It says CS are provided to give both short and long distance sighting of the signal. It doesn't say why.

Any advice of the differences and whether they are interchangeable?


Thanks
A banner repeater signal is NOT a stop signal. Trains may pass it regardless of the displayed aspect (even if it's unlit / black). They are always some distance away from the signal they are repeating. And are provided where there is insufficient sighting distance of the main signal at the line speed of the line.

Banner repeater signals are designed to be visable from a distance.

Co-acting signals are, as others have said, are designed to be fitted very close to the main signal. When showing a red aspect, trains are not normally permitted to pass them unless so instructed by a signaller or hand signaller.
 

Banana

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17 Jun 2016
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You don't have to stop at a Banner Repeater. You do at a a co-actor.
 

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