Permanent Speed Restrictions

[John1976]

I know the difference between an ESR and a TSR but what, if any, is the difference between a TSR and a PSR? If there is why isn't a PSR just marked down as linespeed then as they aren't mentioned in the sectional appendix? Thanks for anyone who can shed some light on this in advance..

 

[pendolino]

I know the difference between an ESR and a TSR but what, if any, is the difference between a TSR and a PSR? If there is why isn't a PSR just marked down as linespeed then as they aren't mentioned in the sectional appendix? Thanks for anyone who can shed some light on this in advance..

I've always taken PSR to mean linespeed but only in an informal sense as 'PSR' is not actually a term in the rule book which only talks about Temporary and Emergency Speed Restrictions and Permissible Line Speeds (enhanced or otherwise). Any speed denoted by yellow boards is still technically a TSR and will be published in the WON for as long as it remains in force, regardless of how long it's in place. (is that the sort of thing you're thinking of?)

 

[The Barlow Boy]

I know the difference between an ESR and a TSR but what, if any, is the difference between a TSR and a PSR? If there is why isn't a PSR just marked down as linespeed then as they aren't mentioned in the sectional appendix? Thanks for anyone who can shed some light on this in advance..

Well, T stands for temporary and P stands for Permanent.

 

[Greeny]

I know the difference between an ESR and a TSR etc

Unless things have changed radically in the last few years PSR’s are published in the Sectional Appendix and when Drivers sign for the route they are conversant with that portion of line and the restrictions on it for example restrictions on curves, on Slow Lines, through junctions, or crossovers. I assume that is what you meant?

BTW, as you have seen there will always be some Members that just love responding to perfectly reasonable questions such as yours with sniping and snotty responses. Don’t rise to it.

G

 

[The Planner]

Any speed denoted by yellow boards is still technically a TSR and will be published in the WON for as long as it remains in force, regardless of how long it's in place. (is that the sort of thing you're thinking of?)

I'm fairly sure now that there is a process where that a TSR has to be converted to a PSR if it has been on for x amount of time with no remedial action. Fixed diamonds are the worst for it.

 

[A-driver]

The TSR at stoats nest junction has been there about a decade and no sign of it bring a PSR. They quite often increase PSRs with upgrade works-eg finsbury park area last month.

I thought PSR was a permissible speed not permanent?

EDIT: Just looked in my rule book and PSR is permissible speed restriction, not permanent if that helps.

 

[pendolino]

I'm fairly sure now that there is a process where that a TSR has to be converted to a PSR if it has been on for x amount of time with no remedial action. Fixed diamonds are the worst for it.

I believe that's the case too. But I've also heard talk of long term TSRs being withdrawn on Christmas Day and then reimposed for Boxing Day so that they can remain TSRs (I don't know if that's true or just mess room talk).

 

[fgwrich]

I'm fairly sure now that there is a process where that a TSR has to be converted to a PSR if it has been on for x amount of time with no remedial action. Fixed diamonds are the worst for it.

There certainly are a few of those around - Basingstokes fairly new diamond crossing on the up fast is one of them - installed in 2007, as is the bridge over the river avon down in Christchurch, Which is changed back up to 60/80? MPH for at least one day in several months, before being reduced back down to TSR of 40 again. But that certainly is the case - i believe it's cheaper to keep it as a TSR than a PSR, and there is a limited number of days on the clock before a TSR has to be changed to a permenant PSR, so the process involves cancelling & removing the TSR for a limited number of days before the reinstating it again.

 

[Robsignals]

There certainly are a few of those around - Basingstokes fairly new diamond crossing on the up fast is one of them - installed in 2007, as is the bridge over the river avon down in Christchurch, Which is changed back up to 60/80? MPH for at least one day in several months, before being reduced back down to TSR of 40 again. But that certainly is the case - i believe it's cheaper to keep it as a TSR than a PSR, and there is a limited number of days on the clock before a TSR has to be changed to a permenant PSR, so the process involves cancelling & removing the TSR for a limited number of days before the reinstating it again.

I don't know but wonder if conversion to PSR requires headways recalculated to check they still comply with the 'Rules of the Route' and, in an extreme case, signals may need repositioning to do so.

 

[KA4C]

I know the difference between an ESR and a TSR but what, if any, is the difference between a TSR and a PSR? If there is why isn't a PSR just marked down as linespeed then as they aren't mentioned in the sectional appendix? Thanks for anyone who can shed some light on this in advance..

A PSR is the permitted speed restriction, in other words the permitted speed for the section of line as published in the Sectional Appendix Table A. in reality, it is a reminder, an aid to the driver of the speed which he/she should know from their route knowledge. if the boarded PSR speed differs to the sectional appendix table A speed (due to an error in boarding) then the SA TA speed applies

 

[Railsigns]

Just looked in my rule book and PSR is permissible speed restriction, not permanent if that helps.

The current Rule Book mentions "Permissible Speeds" (not "Permissible Speed Restrictions" - there's no such thing).

PSR stands for "Permanent Speed Restriction".

There's a subtle difference between those two terms.

The way that speed information is presented in the Sectional Appendix changed significantly in the mid-1990s. Before then, every railway line had a published "Maximum Permissible Speed" and at various places along the length of the route, "Permanent Speed Restrictions" (PSRs) of a lower speed were imposed. PSRs were listed in the Sectional Appendix, with their start and end mileages. A PSR sign was erected at the lineside at the start of each PSR but there was normally no sign marking the end of the PSR, where the Maximum Permissible Speed could be resumed. This was roughly equivalent to the National Speed Limit on the roads, with lower speed limits applying through built-up areas, etc.

Modern Sectional Appendices make no distinction between Maximum Permissible Speed and Permanent Speed Restrictions. Instead, speed information is presented in a more straightforward and continuous manner. The maximum permitted speed on any part of the line is now referred to as the "Permissible Speed". In the Sectional Appendix, a permissible speed value that was previously a "Maximum Permissible Speed" is preceded by an inverted comma (e.g. '70) to indicate that the speed change may not be signed at the lineside. Current practice is to place a speed sign at every change of permissible speed but there are still a great many places where the permissible speed increases and no speed sign is installed.

 

[Greeny]

The current Rule Book mentions "Permissible Speeds" (not "Permissible Speed Restrictions" - there's no such thing).

PSR stands for "Permanent Speed Restriction".

At last, something correct appears - thanks Railsigns, very well put.

G

 

[The Planner]

I don't know but wonder if conversion to PSR requires headways recalculated to check they still comply with the 'Rules of the Route' and, in an extreme case, signals may need repositioning to do so.

Yes, they are looked at and if it ever gets to that stage then you are in the big bucks world of Network Change and another solution is hastily found. You don't mess with the signalling unless you really have to...

 

[Robsignals]

Modern Sectional Appendices make no distinction between Maximum Permissible Speed and Permanent Speed Restrictions. Instead, speed information is presented in a more straightforward and continuous manner. The maximum permitted speed on any part of the line is now referred to as the "Permissible Speed". In the Sectional Appendix, a permissible speed value that was previously a "Maximum Permissible Speed" is preceded by an inverted comma (e.g. '70) to indicate that the speed change may not be signed at the lineside. Current practice is to place a speed sign at every change of permissible speed but there are still a great many places where the permissible speed increases and no speed sign is installed.

For a resignalling scheme Line Speed was jointly agreed by the Track and Signal Engineers but in later BR days costs were saved (fewer signals) by designing for a higher speed and incase there might be a future increase. Coastway West Portslade - Angmering was designed for 100 mph (Worthing - West Worthing would be 75 mph PSR due to signal spacing limited by Xings and pointwork) but Line Speed has stayed at 70 mph.

 

[mr_moo]

The duration for a TSR having to become a PSR is technically set to 6 months, although I think this is the time when you have to start doing the checks and calcs rather than actually change the signs etc. As others have mentioned, there's a lot more to it than just changing the signs so sometimes they stay as TSRs if the change to a PSR is too difficult or costly etc.

I'm interested to hear about Basingtoke - What TSR is on there now? That fixed diamond was designed for 90mph full linespeed on the through route. The old switched diamond that was taken out had had a TSR on it for ages but the new layout was supposed to restore the full functionality.

 

[westcoaster]

The TSR at stoats nest junction has been there about a decade and no sign of it bring a PSR. They quite often increase PSRs with upgrade works-eg finsbury park area last month.

I thought PSR was a permissible speed not permanent?

EDIT: Just looked in my rule book and PSR is permissible speed restriction, not permanent if that helps.

in relation to stoats nest tsr's, the speed from the down fast to the down redhill was 70mph this was reduced to a 60mph tsr which was there for so long it is now a psr at 60mph. In the up direction it is still at 70 mph crossover but with a 60mpf tsr.

 

[Joseph_Locke]

At last, something correct appears - thanks Railsigns, very well put.

G

... but Permanent Speed Restriction is an irrelevant term, as all changes in speed are (or should be) signed on the ground. The days of a route having a Linespeed of 100mph and then only the areas where this did apply being marked went many years ago. If a TSR was made permanent, the Permissible Speed in the Setional appendix and on the signs would be changed.

So, there are only:
- Permissible Speeds (e.g. 90),
- Standard Differential Permissible Speeds (e.g. 60 over 90),
- Non-standard Differential Permissible Speeds (e.g. 60 over 75 MU) and
- Enhanced Permissible Speeds (e.g. 110 over 125 EPS).

Technically there is also such a thing as a Non-standard Differential Enhanced Permissible Speed (e.g. 90 over 110 [221] over 115 [390]), as seen on the WCML.

 

[DarloRich]

I know the difference between an ESR and a TSR but what, if any, is the difference between a TSR and a PSR? If there is why isn't a PSR just marked down as linespeed then as they aren't mentioned in the sectional appendix? Thanks for anyone who can shed some light on this in advance..

I think there might be a slight clue in the title..............

 

[Greeny]

... but Permanent Speed Restriction is an irrelevant term etc.......

Hello Joseph Locke,

As I said in my original post, unless things have changed radically in the last few years a PSR is a Permanent Speed Restriction. To the very best of my knowledge there is no such thing as a Permissible Speed Restriction though I am happy to be corrected if anybody has fact to say so. I think what some people posting here are talking about is the ‘Permissible Speed’ of a line in the Rule Book. Also, I tried to give examples of what I was referring to – e.g. speed restrictions on curves, through junctions, or over structures, where speed had to be reduced on every occasion from the persissible line speed, and was acknowledged when a Driver signed for his route knowledge, irrespective of other conditions which may exist.

What flew up my nose more than some folk making up their own definitions was the unnecessary tone of some of the responses to, what I perceived as, a perfectly reasonable question from the individual that started the thread. I emphasise that I am NOT referring to any of your responses to civil questions which, have always been polite and helpful.

The problem I see when people adopt such attitudes, is that people asking questions will stop asking and make their own answers up which does nobody any good.

Anyhow, thanks for your time and for the comment.

G.

 

[Railsigns]

To the very best of my knowledge there is no such thing as a Permissible Speed Restriction

There is no such thing and if you think about it, it's a nonsensical expression inasmuch as the words "permissible" and "restriction" have almost opposite meanings.

 

[Greeny]

Railsigns - agreed, it is a complete contradiction in terms.

G

 

[Joseph_Locke]

Hello Joseph Locke,

As I said in my original post, unless things have changed radically in the last few years a PSR is a Permanent Speed Restriction. To the very best of my knowledge there is no such thing as a Permissible Speed Restriction though I am happy to be corrected if anybody has fact to say so.

I never said there was such a thing. What I said was that the term PSR is now irrelevant.

I think what some people posting here are talking about is the ‘Permissible Speed’ of a line in the Rule Book.

Permissible speeds do not appear in the Rule Book, and to my knowledge, have never done so.

Also, I tried to give examples of what I was referring to – e.g. speed restrictions on curves, through junctions, or over structures, where speed had to be reduced on every occasion from the persissible line speed, and was acknowledged when a Driver signed for his route knowledge, irrespective of other conditions which may exist.

There is no such thing as linespeed (in terms of a speed which applies when no other restriction is present) as all speeds are signed. Therefore every signed speed is a Permanent Speed Restriction, making the need for the term go away. The term used in standards to describe the speed at which trains may travel is Permissible Speed.

I emphasise that I am NOT referring to any of your responses to civil questions which, have always been polite and helpful.

Thank you.

The problem I see when people adopt such attitudes, is that people asking questions will stop asking and make their own answers up which does nobody any good.

Anyhow, thanks for your time and for the comment.

G.

 

[A-driver]

Getting a bit confused by your post but permissible speeds certainly do appear in the rule book-module sp.

The white circle, red boarder, black number (like road side speeds) is a permissible speed sign.

 

[transmanche]

FWIW, I've just looked at Module SP of the Rule Book (dated 2008).

It refers to 'Permissible Speed' (and 'Enhanced Permissible Speed') as shown in the relevant Sectional Appendix. It also refers to 'Temporary Speed Restriction' and 'Emergency Speed Restriction'.

It does not mention 'Permanent Speed Restriction' (or 'Permissible Speed Restriction').

 

[Joseph_Locke]

FWIW, I've just looked at Module SP of the Rule Book (dated 2008).

It refers to 'Permissible Speed' (and 'Enhanced Permissible Speed') as shown in the relevant Sectional Appendix. It also refers to 'Temporary Speed Restriction' and 'Emergency Speed Restriction'.

It does not mention 'Permanent Speed Restriction' (or 'Permissible Speed Restriction').

Aaargh! We're agreeing! Stop already!

 

[miikey]

A TSR is published in the WON (Weekly Operating Notice) but not in the Sectional Appendix, therefore its not permanent and can be removed effectively anytime. However if the TSR is removed before its published end date in the WON its called a SPATE (Speed Previously Advised Terminated Early). Where as a PSR (Perminant Speed Restriction) is not published in the WON but is published in the Sectional Appendix, therefore making it permanent. PSR is not a Permissable Speed Restriction, you may be thinking of EPS (Enhanced Permissable Speed) for special units.

 

[John1976]

Thanks for all the replies, v informative. Good to chuck a bone out there and see how it gets chewed so to speak!
If a PSR is published in the Sectional Appendix what differentiates that from the linespeed which is also printed in the S.A? Is the advertised linespeed in effect one continuous PSR?
I know it all sounds a bit perdantic and I suppose it is for which I can only apologise haha...

 

[Joseph_Locke]

Thanks for all the replies, v informative. Good to chuck a bone out there and see how it gets chewed so to speak!
If a PSR is published in the Sectional Appendix what differentiates that from the linespeed which is also printed in the S.A? Is the advertised linespeed in effect one continuous PSR?
I know it all sounds a bit perdantic and I suppose it is for which I can only apologise haha...

If its in the SA its a permissible speed (PS) - yes, the SA speeds are effectively one big PSR (so to speak), but that means "PSR" is a redundant term ...

 

[Shimbleshanks]

The TSR at stoats nest junction has been there about a decade and no sign of it bring a PSR. They quite often increase PSRs with upgrade works-eg finsbury park area last month.

I thought PSR was a permissible speed not permanent?

EDIT: Just looked in my rule book and PSR is permissible speed restriction, not permanent if that helps.

We were told by a Southern Railway representative at the last East Surrey transport Committee that there will be engineering work this Xmas on the Stoats Nest crossings to restore them back to full speed (70mph on the turnout, I think).

 

[Ploughman]

But will they have the money to remove the TSR?

Recent work on the Esk valley line replacing 4 bridges is I believe still under a TSR that cannot be removed due to the lack of £50K