Indusi (Tyne & Wear Metro)

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Nick82

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Could any one help with a link for some information regarding the signalling system used for the Tyne & Wear Metro
 
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MarkyT

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Could any one help with a link for some information regarding the signalling system used for the Tyne & Wear Metro

Here is a good description (in English) of the system as used in Germany:

http://www.sh1.org/eisenbahn/rindusi.htm

Indusi is similar in principle to TPWS as it has an over-speed transponder on approach to, and a train stop at the signal. These are both designed to control speed and stop a train within the overlap. Indusi differs from TPWS by enforcing further deceleration within a specified distance of the over-speed equipment even after passing without tripping.

There's also a transponder for a caution aspect similar to UK AWS, but it's at the signal rather than on its approach. At caution, it doesn't just require driver acknowledgement, but like the over speed it enforces further deceleration.

The system is more fail-safe than TPWS. Even with a trackside signalling power supply outage a train will still receive warnings and interventions.
 

142094

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Just for clarification, repeater signals on the normal Metro network do not have any sort of Indusi magnet fitted to them. As a result the driver doesn't receive an in cab notification of a caution aspect like with AWS. Therefore it is up to the driver to make a decision when to start braking for a danger aspect.

In certain locations there are speed magnets which will force an emergency brake application if the train is travelling too fast, but these are not fitted to signals.
 

MarkyT

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Just for clarification, repeater signals on the normal Metro network do not have any sort of Indusi magnet fitted to them. As a result the driver doesn't receive an in cab notification of a caution aspect like with AWS. Therefore it is up to the driver to make a decision when to start braking for a danger aspect.

In certain locations there are speed magnets which will force an emergency brake application if the train is travelling too fast, but these are not fitted to signals.

Whilst they use a cautionary yellow aspect in the 3-aspect continuously signalled sections, T&W Metro has fixed distant warning boards on approach to isolated two aspect signals covering the majority of the surface sections. These take the form of a highway-inspired red-bordered triangular plate containing the image of a signal supplemented by another plate beneath stating the distance to the signal. Signals are mostly at the end of platforms, where all trains stop, so the distant boards also effectively provide a useful station approach reminder. With the Excellent braking capability of the tram-derived vehicles and relatively low maximum speed on the Metro, trains can usually be controlled adequately within the sighting distance of the signal, and can always be relied on to stop within the overlap if tripped at the Indusi overspeed equipment. Thus a separate distant magnet is not required.
 

edwin_m

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I should just mention that there are (or at least were a few years ago) some two-aspect repeaters on the Metro, protecting two-aspect stop signals where these were needed between some of the more widely-spaced stations.
 

swt_passenger

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Is it correct to refer to the Metro's whole signalling system as 'Indusi' or should that term just describe the protection system?

(In the context of the OP's first question.)
 

MarkyT

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Is it correct to refer to the Metro's whole signalling system as 'Indusi' or should that term just describe the protection system?

Indusi is just the protection system. The underlying signalling is a fairly typical UK colour light system, based on mainline TCB principles.
 

142094

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Whilst they use a cautionary yellow aspect in the 3-aspect continuously signalled sections, T&W Metro has fixed distant warning boards on approach to isolated two aspect signals covering the majority of the surface sections. These take the form of a highway-inspired red-bordered triangular plate containing the image of a signal supplemented by another plate beneath stating the distance to the signal. Signals are mostly at the end of platforms, where all trains stop, so the distant boards also effectively provide a useful station approach reminder. With the Excellent braking capability of the tram-derived vehicles and relatively low maximum speed on the Metro, trains can usually be controlled adequately within the sighting distance of the signal, and can always be relied on to stop within the overlap if tripped at the Indusi overspeed equipment. Thus a separate distant magnet is not required.

My post was aimed at the section in your first post regarding the transponder fitted to repeater signals. There is no idication to a driver or is there any speed enforcement, in the end it is down to the driver to control the speed of the train and prevent a Spad. Indusi does not bring about a brake application unless a signal is passed at danger. Also the vast majority of the system is signalled with 2 aspect signals. Even where there are three aspect signals, these only have an Indusi magnet attached to them which do not show indications on caution aspects.

Taking an extreme example, when leaving East Boldon on the Down, if there is a freight waiting to go through the road to Tyne Dock, the platform starting signal can give a single yellow to a driver. There is just about enough distance to get upto 80 kmh before the next signal. Indusi does not limit a train's speed in this case, so a driver has to be aware to not have a Start on Yellow Spad.
 

MarkyT

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My post was aimed at the section in your first post regarding the transponder fitted to repeater signals. There is no idication to a driver or is there any speed enforcement, in the end it is down to the driver to control the speed of the train and prevent a Spad. Indusi does not bring about a brake application unless a signal is passed at danger. Also the vast majority of the system is signalled with 2 aspect signals. Even where there are three aspect signals, these only have an Indusi magnet attached to them which do not show indications on caution aspects.

Taking an extreme example, when leaving East Boldon on the Down, if there is a freight waiting to go through the road to Tyne Dock, the platform starting signal can give a single yellow to a driver. There is just about enough distance to get up to 80 kmh before the next signal. Indusi does not limit a train's speed in this case, so a driver has to be aware to not have a Start on Yellow Spad.

So the Indusi system is used as a magnetic train stop pure and simple. Presumably a fully braked protection overlap beyond a red signal is applied as with the mechanical train stop system on LU. I expect the trains' emergency braking is very good from the fairly modest maximum speed, so overlaps needn't be particularly long to provide full protection.
 

edwin_m

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So the Indusi system is used as a magnetic train stop pure and simple. Presumably a fully braked protection overlap beyond a red signal is applied as with the mechanical train stop system on LU. I expect the trains' emergency braking is very good from the fairly modest maximum speed, so overlaps needn't be particularly long to provide full protection.

They have track brakes similar to those of trams, for emergency use only. I don't know the exact deceleration but it is likely to be at least twice that of any train.
 

142094

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So the Indusi system is used as a magnetic train stop pure and simple. Presumably a fully braked protection overlap beyond a red signal is applied as with the mechanical train stop system on LU. I expect the trains' emergency braking is very good from the fairly modest maximum speed, so overlaps needn't be particularly long to provide full protection.

150m is the stopping distance when travelling at full speed under good rail conditions when the emergency track brake is applied.
--- old post above --- --- new post below ---
Also for clarification, the system does have Indusi magnets to control speed on certain approaches to level crossings and terminus stations, but these are generally not associated with signals. Speed magnets are activated by treadles and/or track circuits.
 

MarkyT

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Speed magnets are activated by treadles and/or track circuits.

Are these simple timed speed traps with a train-stop or do they use the multifrequency capability of indusi to send particular speed codes to the train?
 

142094

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Are these simple timed speed traps with a train-stop or do they use the multifrequency capability of indusi to send particular speed codes to the train?

Just timed sections which start when the train wheel passes over the treadle or goes into the appropriate track circuit. As far as I know the magnets on the track can only be set to two frequencies (i.e. clear or danger).
 
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