Couple of DLR questions

[Barn]

I've taken to using the DLR quite frequently. Two things have got me wondering:

1 - What decides whether the train is operated from the front or not? Is it simply a matter of the PSA's discretion, or are there times or circumstances when the PSA has to sit at the front or has to roam the train? I'm not referring to the very rare situations in which the PSA actually drives; just where he/she operates the doors.

2 - Except when the PSA is at the front and in reach of the emergency stop plunger, is it correct to assume that there is no system to detect and brake for persons or obstructions on the line?

 

[rebmcr]

I've taken to using the DLR quite frequently. Two things have got me wondering:

1 - What decides whether the train is operated from the front or not? Is it simply a matter of the PSA's discretion, or are there times or circumstances when the PSA has to sit at the front or has to roam the train? I'm not referring to the very rare situations in which the PSA actually drives; just where he/she operates the doors.

If the PSA is at the front, he or she is driving. This is entirely their choice, except when the signalling system is not operating correctly.

The PSA always operates the doors, no matter which position they are in (either from the driving console or from a door panel).

2 - Except when the PSA is at the front and in reach of the emergency stop plunger, is it correct to assume that there is no system to detect and brake for persons or obstructions on the line?

Not sure about this one. I would expect there to be an emergency stop control on the door panel, but I'm sure someone will be along to confirm one way or another.

 

[Barn]

If the PSA is at the front, he or she is driving. This is entirely their choice, except when the signalling system is not operating correctly.

The PSA always operates the doors, no matter which position they are in (either from the driving console or from a door panel).

Yes, my reference to 'driving' wasn't intended to minimize the duties of the PSA. I'm trying to distinguish between the scenarios where the PSA actually controls the movement of the train (where they obviously must be at the front) from situations in which they operate the doors and give the movement authority (which can be from the front or from any door).

Are there any scenarios whereby the train has to be driven from the front, such as after a certain time at night, through certain stations, when the train takes on a large number of passengers, in certain weathers, first and last train, etc?

Or is it entirely up to the PSA's discretion?

 

[SpacePhoenix]

I think the PSA might have driven one in manual once that i was on, between Pudding Mill Lane and Stratford, there was a fire very near to the lineside.

Looked at a picture via a google image search of the door controls, couldn't see estop button. Could the PSA's radio be "assigned" to the unit, with a emergency button on it somewhere?

 

[Busaholic]

I've only been on the DLR a couple of dozen times, from the date of its opening to probably my last time about five years ago, but I experienced the train being driven on four or five occasions: the first time was definitely in extremis, on the first weekday of service to Stratford, but on the others the driver appeared to have made his own decision.

 

[SpacePhoenix]

Do the PSAs have to clock up a certain number of hours per month or year driving them manually to keep up their skills?

 

[edwin_m]

I believe there is a mode where the PSA sits at the front but doesn't actually drive, just operates the button that starts the automatic driving to the next station.

 

[Barn]

I believe there is a mode where the PSA sits at the front but doesn't actually drive, just operates the button that starts the automatic driving to the next station.

Yes, exactly, and what really lay behind my question was that thus mode appears to have become the new default operation, at least on my twice daily trips. It seems to be by exception that the PSA wanders the train. Not a complaint, just curious.

 

[Smod]

I travel regularly on the DLR. Off peak the operators almost always operate the trains from the door panels. However, in the peak hours they almost always operate the train from the front. Presumably that's because it's too crowded around the doors to do otherwise.

It's also common for the late night trains to be operated from the front.

I have also known the operators to be instructed by their control to operate the trains from the front. Not sure if this was a technical issue, or if they wanted the operators to be watching out for something.

 

[bramling]

I travel regularly on the DLR. Off peak the operators almost always operate the trains from the door panels. However, in the peak hours they almost always operate the train from the front. Presumably that's because it's too crowded around the doors to do otherwise.

It's also common for the late night trains to be operated from the front.

I have also known the operators to be instructed by their control to operate the trains from the front. Not sure if this was a technical issue, or if they wanted the operators to be watching out for something.

If it's anything like the Seltrac on the Underground, I would expect them to be required to be positioned at the front if staff are working on the track for any reason. I'm sure I recall being told that in the event of a failure of CCTV viewing of a station then same would apply - presumably as the control room would no longer have sight of anyone potentially on the track.

 

[theking]

The psa can stop the train from the door control panel aswell as the controllers having emergency push buttons to stop all train's on a specific section of track.


There is no detection equpiment on the front of trains so if something is trackside and not reported or seen by the psa it will get run over. Sad incident happened at Stratford where a women started fitting fell trackside and was killed by the train.

Psa operate from the front compulsory thursday and Friday after 2000 and it's their choice on Saturday and Sundays after 2000.

Most peak services going in the busy direction the psa will operate from the front for safety reasons.

Various other reasons for them to operate from the front some being personel trackside, failure of cctv, passenger alarms or the end gate alarms especially in the tunnel sections.

 

[jopsuk]

if the primary reason for operating from the front is potential for passengers falling from platforms, I do wonder if platform edge doors have ever been considered for the system?

 

[Taunton]

We nowadays live along the DLR.

Operation from the front panel always happens with empty trains to/from the depot, so the whistle can be sounded when non-stopping stations.

Likewise maintenance crews do work lineside during operating hours, when they are in a section the PSA is advised and has to operate from the front.

I'm not clear what the emergency points on the platforms do, should one witness an incident at a station. I used to think they stopped the trains, but after the report into the All Saints accident it appeared they did not.

 

[47513 Severn]

In my own observations they tend to operate from the front at busy times when the train is going to be packed. I presume this is because it would be difficult to move around the train or even move from one side of the train to another with a full load.

Operating from the front also slightly speeds the disparch process as the PSA can close all the doors at once, cutting out the local door closing stage.

 

[Clip]

if the primary reason for operating from the front is potential for passengers falling from platforms, I do wonder if platform edge doors have ever been considered for the system?

Its not for that potential at all its just easier at times if they have track workers somewhere and some stations may require them to do so. Sometimes they just fancy a rest from being on their feet

They very VERY rarely drive them as such on the mainline and mainly do the doors as posted above from that position.

They do manual to and form the depots and its normally the technicians who will engage in mainline driving whilst taking a vehicle out of service.

 

[jopsuk]

I presume this is because it would be difficult to move around the train or even move from one side of the train to another with a full load.

.

also means that they aren't occupying circulating space at the doorways

 

[Taunton]

Another reason for operating from the front in the winter is that it's warmer than working from the doors ...

 

[BestWestern]

So the PSAs can decide whether they will drive the train manually, or whether to leave it to run automatically? That's a very liberal policy!

 

[Taunton]

No. They can decide whether to push the Doors Closed button from the doorway or from the front desk. That's quite different.

 

[BestWestern]

No. They can decide whether to push the Doors Closed button from the doorway or from the front desk. That's quite different.

Ah! I had read it as driving!

 

[Ianno87]

I've seen trains driven manually through closed stations.

Train operates in automatic mode until just before the closed station is reached. The PSA then opens up the front control panel to manually take over driving through the closed station (overriding the computer that wants to stop the train as per the timetable). Once the station has been passed, the train is put back into automatic mode whereby the train resumes normal working to the next station.

 

[BestWestern]

Is there an equivalent to TPWS in force to provide a safeguard under manual operation? Incidentally, what was the cause of the infamous Island Gardens 'cliffhanger' back in 87?!

 

[theking]

Is there an equivalent to TPWS in force to provide a safeguard under manual operation? Incidentally, what was the cause of the infamous Island Gardens 'cliffhanger' back in 87?!

There are three driving modes a psa can operate in.

Automatic train protection manual (atpm)

This mode has the signalling system the psa drives the train using the power stick and controls the speed by adhering to the target speed indicator. It also has the protection of the collision avoidance zone boudries and timetabling so the psa knows when to depart the train. Also does not let you enable doors without being at the correct docking position and protects against wrong side opening also cannot reverse in this mode.

The second mode is emergency shunt

This is completely manual the psa has complete control of all driving motions forward and reverse the psa can also enable doors at any time. Normally used when the train overshoots it's correct docking position or when the train loses communication with the signalling system. Maximum speed 20kph

The third is push mode
This is a suped up version of shunt normally used in rescuing a failed unit.

 

[SpacePhoenix]

Automatic train protection manual (atpm)

This mode has the signalling system the psa drives the train using the power stick and controls the speed by adhering to the target speed indicator. It also has the protection of the collision avoidance zone boudries and timetabling so the psa knows when to depart the train. Also does not let you enable doors without being at the correct docking position and protects against wrong side opening also cannot reverse in this mode.

When they're driving manually in that mode, how large is the docking position? Do they have much leeway either side of it?

 

[ag51ruk]

Do the PSAs still do ticket/Oyster checks? When the DLR first opened, I'd get checked by the Train Captain on almost every trip but of course the trains were shorter and less busy in those days.

On my occasional DLR trips now, I haven't seen either the PSA do checks, or any other revenue protection activity on train or at stations.

 

[edwin_m]

Had a revenue check (or at least a scan of the contactless card) by the PSA when I was there a couple of weeks ago.

 

[theking]

When they're driving manually in that mode, how large is the docking position? Do they have much leeway either side of it?

Not sure if you have seen a docking board on the dlr?

But the coupler should be aligned with the diamond in the middle of the docking board I would say the diamond is roughly the size of the green docking position markers on the underground maybe slightly smaller.

Anything past the diamond the train will emergency brake and the psa has to call the control centre this is due to the fact the train will need to be reversed in emergency shunt so that the coupler is over the diamond so doors can be enabled.

In auto or atmp if the train overshoots the docking mark nothing can be done by the control centre if the train is to service the station. They can lift the emergency brake application but the train will continue to the next station.

 

[Smod]

In response to the query about revenue checks, as a regular traveller I reckon that the operator seems to do a ticket check on around one service in three off peak. In the peak hour, however, it would be impossible.

Occasionally there are outbreaks of mass inspectors at stations, but not very often.

 

[Taunton]

Anything past the diamond the train will emergency brake and the psa has to call the control centre this is due to the fact the train will need to be reversed in emergency shunt so that the coupler is over the diamond so doors can be enabled.

The train has to dock precisely in the platform. This is not because there are platform doors, but given the current collection is under-running (only one in Britain?), this means the collector shoes on the train point upwards and are live. The conductor rail may be on the far side from the platform but the shoes on the platform side will be live, and just below platform level. To guard against a passenger falling down the gap, collector shoe guards are positioned over the positions where the train stops. They are only short length, so the train must stop precisely to ensure the shoes are under the guards.

Do the PSAs still do ticket/Oyster checks? When the DLR first opened, I'd get checked by the Train Captain on almost every trip

Still done. When it was single car and one Train Captain that was straightforward. Now it is three cars but still one staff member it still goes on but up and down the train.

Checks still work out quite frequent. I am surprised at the small amount of fare bilking that seems to take place.

 

[Barn]

Ok, follow up question! The left-hand console contains the train operation controls for the PSA. What's on the console on the right?