TRTS buttons

[najaB]

Would it be fair to say that TRTS buttons at stations are used more as 'Train Rolling To a Stop' than 'Train Ready To Start ' these days? I often see platform staff jabbing away at them before the doors are even open.

 

[Dhassell]

I guess it depends on staff members, I have observed many at Bristol Temple Meads only pressing them a minute or two from departure. I guess it also depends on how long the train is gonna be stood at the station for.

 

[najaB]

I guess it also depends on how long the train is gonna be stood at the station for.

I've seen them pressing the button before the train has stopped when when there is a five plus minute booked stop.

 

[LowLevel]

They're meant to be used two minutes before departure but many are provided simply as a 'wake up the signaller' appliance on busy workstations nowadays. If we had a move that was an in/out stop and we hadn't got the road we used to press them as soon as the track circuit was occupied which had the desired effect.

Otherwise they're mostly used at busy locations or ones with things like level crossings to trigger - I work through a few mandatory TRTS stations, then others have them provided to be used if necessary. At the former if you don't bell out even on a through train you won't get the signal, at the latter you might not need to give TRTS. Ely, Lincoln, Liverpool Lime Street and Norwich are examples of the former, Derby and Leicester the latter.

 

[TheEdge]

Officially they are to be used 2-3 minutes before departure. Saying that I'll jab at them if I'm after a quick turnaround.

Lets say the xx:40 arrival to form the xx:45 Norwich - Sheringham is pulling in at xx:43. I'll be pushing up for that before its stopped so once everyone is on and we are truly ready to start I already have the road and hopefully as close a right time start as possible.

 

[LowLevel]

That said people who actually jab at them like they're playing a 1980s video game are the S&T's worst nightmare - where I used to work had an older relay based interlocking and despite continued warnings some members of staff just used to jab the buttons which produced no effect whatsoever in the PSB, then report them as faulty. It doesn't give enough time for the relay to pick, which is why they say 'press and hold for at least x seconds'.

Pressing it multiple times gives no more than one indication for one train on the panel or workstation anyway, unless you're dealing with particularly vintage kit (we have it at Boston) which will just buzz like a demented mosquito repeatedly and irritate the signalman.

 

[tsr]

I was always taught to hold the button/switch for 2 seconds, 2 minutes before departure, as a matter of fundamental route-learning principle for required locations. It's a shame this (or any local variant) is perhaps not taught so clearly as a rule elsewhere.

A couple of unrelated points:
- At a couple of places I regularly work, the TRTS isn't a button or t-key switch (usual) but another type of key-switch, for a specialist key only held by platform staff. How common is this?
- Can anyone beat the ludicrous TRTS label at Oxted for "Platform 3 Up/Down"? Platform 3 is a 3-coach bay platform, accessed since [eternity] from the Down end only, with no signalled moves within the bay in the Up direction, meaning it is not possible to give TRTS on the Up without the effect being that you are asking if you could kindly crash into the buffers.

 

[LowLevel]

Key switches seem to have been popular at one point, where I work the TRTS was on a key at Liverpool Lime Street (now largely if not entirely replaced by normal boxes the S&T locally have helpfully customised to have white LEDs on the side that light up when the signal clears where OFF indicators aren't provided as the old key switches did), and at Ely. RA only is done by a key at Manchester Piccadilly with TRTS being a button.

Everywhere else I work is some variety of older or newer button. The Nottingham ones that are platform staff only helpfully have the button light up blue when the TRTS has been registered.

 

[323235]

Interestingly enough I was at Reading today and noticed the dispatcher using the TRTS just as we stopped at the platform. The rode was immediately given.

 

[TEW]

There's not a lot of consistency is there. None of the ones on routes I sign need a key, they're all buttons. They have varying instructions on the length of time you have to press them for, or often no instructions. There is one which you have to press for at least x seconds but not more than you seconds, I can't remember the exact figures off the top of my head! Some will light up to indicate they've operated, some don't. 2 minutes before departure is the general rule for the time to operate them, but at some locations you have to press it before that to allow for level crossings to operate. And the TRTS at Chessington South gives the signal as soon as it is pressed, and it is acceptable to press it as soon as you arrive, even though that's 15 minutes before departure. Some very usefully don't state on them which signal they apply to, or just state the signal number and not direction, which isn't always much help on a bi-directional platform where the signal numbers don't follow a logical sequence.

 

[sarahj]

I like the ones at Portsmouth and Southsea that have a little light that comes one. At some stations you press them and wonder if It worked. Some places are random, you go to press it and it changes, but other times you hear of delays as it was not pushed. :-x

 

[MarkyT]

That said people who actually jab at them like they're playing a 1980s video game are the S&T's worst nightmare - where I used to work had an older relay based interlocking and despite continued warnings some members of staff just used to jab the buttons which produced no effect whatsoever in the PSB, then report them as faulty. It doesn't give enough time for the relay to pick, which is why they say 'press and hold for at least x seconds'.

Pressing it multiple times gives no more than one indication for one train on the panel or workstation anyway, unless you're dealing with particularly vintage kit (we have it at Boston) which will just buzz like a demented mosquito repeatedly and irritate the signalman.

Will not do any damage, just won't get you anywhere faster, like button controlled pedestrian signals on roads. If the buzzer keeps going off as at you say it does at Boston, then that's not going to get you on the right side of the signaller!

I was always taught to hold the button/switch for 2 seconds, 2 minutes before departure, as a matter of fundamtental route-learning principle for required locations. It's a shame this (or any local variant) is perhaps not taught so clearly as a rule elsewhere.

The 2 seconds hold in advice is more to cater for slower acting electronic systems such as SSI which react to inputs more slowly than relays, which can be virtually instantaneous. SSI does a repeating sequential scan around all its input module address on the particular trackside datalink subsystem, taking about a second or more in total. A 'quick jab' and release on the button could very easily miss the particular input's allocated time slot in the scan, so it will be missed.

 

[Bromley boy]

There's not a lot of consistency is there. None of the ones on routes I sign need a key, they're all buttons. They have varying instructions on the length of time you have to press them for, or often no instructions. There is one which you have to press for at least x seconds but not more than you seconds, I can't remember the exact figures off the top of my head! Some will light up to indicate they've operated, some don't. 2 minutes before departure is the general rule for the time to operate them, but at some locations you have to press it before that to allow for level crossings to operate. And the TRTS at Chessington South gives the signal as soon as it is pressed, and it is acceptable to press it as soon as you arrive, even though that's 15 minutes before departure. Some very usefully don't state on them which signal they apply to, or just state the signal number and not direction, which isn't always much help on a bi-directional platform where the signal numbers don't follow a logical sequence.

At one of our locations we have "donkeys dicks " with the TRTS buttons on rubber poles extended up to cab height, accessed by leaning out of the driver's window. Really awkward/stiff to push but a light illuminates to confirm the indication has been sent to the signaller.

 

[MarkyT]

At one of our locations we have "donkeys dicks " with the TRTS buttons on rubber poles extended up to cab height, accessed by leaning out of the driver's window. Really awkward/stiff to push but a light illuminates to confirm the indication has been sent to the signaller.

The 'donkeys dicks' were based on a traditional LUL design.

 

[LowLevel]

Will not do any damage, just won't get you anywhere faster, like button controlled pedestrian signals on roads. If the buzzer keeps going off as at you say it does at Boston, then that's not going to get you on the right side of the signaller!



The 2 seconds hold in advice is more to cater for slower acting electronic systems such as SSI which react to inputs more slowly than relays, which can be virtually instantaneous. SSI does a repeating sequential scan around all its input module address on the particular trackside datalink subsystem, taking about a second or more in total. A 'quick jab' and release on the button could very easily miss the particular input's allocated time slot in the scan, so it will be missed.

It's not so much damage, more being constantly called out to non existent faults through misuse they used to hate

 

[Shaw S Hunter]

Would it be fair to say that TRTS buttons at stations are used more as 'Train Rolling To a Stop' than 'Train Ready To Start ' these days? I often see platform staff jabbing away at them before the doors are even open.

Unlikely to happen with the train crew operated ones at Blackpool North!

At a couple of places I regularly work, the TRTS isn't a button or t-key switch (usual) but another type of key-switch, for a specialist key only held by platform staff. How common is this?

Apart from non-stopping trains (ie freights) this happens for every move at Manchester Victoria. Given how busy the platforms are, especially through roads 3-6, I think the platform staff there do a cracking job.

 

[SpacePhoenix]

Is it very common (if at all) for the route to be programmed in, then as soon as the TRTS is pressed the route gets immediately activated (signals and points set), provided there's no conflicting route already active?

 

[GB]

ARS should take care of that.

 

[carriageline]

Will not do any damage, just won't get you anywhere faster, like button controlled pedestrian signals on roads. If the buzzer keeps going off as at you say it does at Boston, then that's not going to get you on the right side of the signaller!



The 2 seconds hold in advice is more to cater for slower acting electronic systems such as SSI which react to inputs more slowly than relays, which can be virtually instantaneous. SSI does a repeating sequential scan around all its input module address on the particular trackside datalink subsystem, taking about a second or more in total. A 'quick jab' and release on the button could very easily miss the particular input's allocated time slot in the scan, so it will be missed.

Aha! You say that, but one of our new SSI interlockings has one of the fastest interlockings I've ever worked, on either workstation or panel! It's very close to being instant! But they don't use trackside modules, but something called object controllers + zone controllere. And they use IP addresses too! Clever kit to be honest.


Sent from my iPhone using Tapatalk

 

[edwin_m]

Aha! You say that, but one of our new SSI interlockings has one of the fastest interlockings I've ever worked, on either workstation or panel! It's very close to being instant! But they don't use trackside modules, but something called object controllers + zone controllere. And they use IP addresses too! Clever kit to be honest.

In that case it's not strictly a SSI, but one of the newer Computer Based Interlockings that has some SSI compatibility. Some of these still do use the SSI trackside modules, but if so they would be constrained by the SSI cycle timings which as suggested above will only scan an indication every second or so. Which wasn't bad in the 1980s when SSI was first introduced, but is looking a bit slow compared to the computers of today!

 

[MarkyT]

In that case it's not strictly a SSI, but one of the newer Computer Based Interlockings that has some SSI compatibility. Some of these still do use the SSI trackside modules, but if so they would be constrained by the SSI cycle timings which as suggested above will only scan an indication every second or so. Which wasn't bad in the 1980s when SSI was first introduced, but is looking a bit slow compared to the computers of today!

I understand at least one of the latest successor interlockings is able to support either the legacy SSI datalinks or a more modern faster communications protocol, even a mixture of the two in the same system if necessary. With its much larger address and processing capability, such a new cubicle can replace a series of old SSIs, directly taking over their existing trackside datalinks and equipment, then add further control area extensions using the newer protocols and object controllers. I hope I'm wrong but I'm a little worried the new developments might represent a drift towards a proprietary lock in, something SSI was deliberately engineered to avoid with at least the possibility of mixing different manufacturers products being designed in.

 

[carriageline]

For those interested, it's a WestLock interlocking if that helps answer or be able to explain?


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[G0ORC]

When I worked in Derby PSB in the late 80s and early 90s TRTS buttons were a source of much friction between the PSB and station staff.

As some on here have said, they were pushed even before the train had stopped. This was common practice too at Derby, were the majority of trains took relief. There were innumerable time the TRTS button was pressed and a route set, only to find that there was no forward driver or guard/conductor on the train. There was a huge amount of delay this caused by waiting with a signal off for 5 min, then being advised that the train couldn't proceed and then the route being cancelled, waiting for a 2 min time out before another route could be set.

Even at times of disruption when forward crews weren't in the right place at the right time this happened, despite station staff being advised beforehand.

The station staff would argue that it meant "station duties complete" - we argued that the train couldn't be ready to start if it hadn't got a driver on it. We never reached a consensus view.

Poor practice if you ask me. I don't know how really busy London termini get on these days in times of disruption. Do they check all crew are on board before pressing the TRTS? I can just imagine what would happen if routes were set at Waterloo or Victoria and the train didn't leave promptly.

 

[SpacePhoenix]

Do they get pressed for one long press or are there various "bell codes" used?

 

[LowLevel]

Nowadays they say for originating services you should check the train is crewed and lights correct before 'belling out'.

The ones we belled out for straight away were in/out through services with no crew change etc where you hadn't got the road and the dwell time was only a minute anyway. Defensive driving now means a train coming in on a red creeps up to it which can be enough to delay it as it'll already have struck in as arrived.

The system depends on what you get when you press the button but at most locations you get a lamp light up/indication on the screen and/or a buzzer, just once. At Boston for example it buzzes each time you press the button so there are (simple) codes - one buzz for ready, and two buzzes for not or cancel.

 

[edwin_m]

Do they get pressed for one long press or are there various "bell codes" used?

They only register once, illuminating a light on the panel or VDU equivalent. The ones I have seen stay lit until the signal is cleared so there is no scope to use them for more sophisticated communication.

 

[G0ORC]

They only register once, illuminating a light on the panel or VDU equivalent. The ones I have seen stay lit until the signal is cleared so there is no scope to use them for more sophisticated communication.

Agreed - if a TRTS button was pressed in error, then a route had to be set, the signal clear and then the route cancelled in order to extinguish the TRTS indication. There was no other way.

 

[MarkyT]

Agreed - if a TRTS button was pressed in error, then a route had to be set, the signal clear and then the route cancelled in order to extinguish the TRTS indication. There was no other way.

Perhaps it would be a useful feature to have a cancelling button on the platform as well. That would avoid the time delays inherent in unneccessary route setting and cancelling (thus allowing the TRTS to be used normally again easily once the train really was ready) The cancelling device could also be used as an emergency signal replacement as well, if operated after the signal had cleared, say if the platform attendant noticed someone or something caught in doors or trapped between train and platform for instance.

 

[edwin_m]

Perhaps it would be a useful feature to have a cancelling button on the platform as well. That would avoid the time delays inherent in unneccessary route setting and cancelling (thus allowing the TRTS to be used normally again easily once the train really was ready) The cancelling device could also be used as an emergency signal replacement as well, if operated after the signal had cleared, say if the platform attendant noticed someone or something caught in doors or trapped between train and platform for instance.

More useful for an emergency, and probably easier to do, would be a button to operate flashing lights on the trackside, which would be visible to the driver even after passing the signal. These are (or used to be) provided on Tyne and Wear Metro.

 

[Phil.]

Because they're either not explained properly or the person receiving the explanation hasn't properly understood platform staff get the idea the TRTS buttons are "call for the road" buttons.
They are there to indicate to a signalman in a 'box that may be thirty miles away and therefore has do idea what's happening at Little Dribbling that the Train is ReadyTo Start.
That is the driver is on as well as the guard(if provided), the doors are closed and when the signal is cleared the train will depart.
What shouldn't - and oft does - is the TRTS button is operated, the signal clears and then the signalman is told, "we haven't got a driver/guard/the doors won't close etc".