Manchester Piccadilly OHLE question.

[TravisM]

I was talking to a friend of mine about Manchester Piccadilly station in the mid 70’s, which had both 1500V DC and 25Kv AC overhead.  Obviously common sense prevailed in keeping the two voltages separate, but I’m pretty sure when travelling on DMU from Guide Bridge, it was routed off the DC lines and onto a platform that carried 25Kv AC.

 

I just wonder if anyone could clarify this?

[jamie92208]

If I remember correctly there were either 2 or three platforms that had 1500 DC OHLE all on the Guide Bridge side of the station.  The other platforms were all wired for 25 KV AC.  I remember the DC EMU's that worked the Hadfield/Glossop service.  When the Woodhead line closed the Hadfield lines were converted to AC with the OHLE left in place but the insulators changed.  

 

Jamie

[DY444]

It's quite simple.  There were crossovers connecting the DC and AC lines on the approach to Piccadilly allowing non-electric trains to cross.  I vaguely remember there being 3 crossovers in total between lines on the two systems;  two facing trains approaching from Ardwick and one facing trains approaching from Longsight.

 

Obviously the two ole systems were isolated from each other at the crossovers.  There are lots of stories of electric trains going bang when accidentally being routed across the boundary but I suspect most of those are apocryphal.   

[pendlerail]

I am sure I have read somewhere that two platforms were dual voltage switched over by the signaller 5 & 6 from memory

[Jeremy Cumberland]

2 hours ago, pendlerail said:

I am sure I have read somewhere that two platforms were dual voltage switched over by the signaller 5 & 6 from memory

I had always assumed that 1-4 were dc and the rest were ac

 

Looking at the track plan I have, I suppose it would be possible to switch 5-7 (6 came off 7), involving just one crossover between the Ardwick and Longsight lines, but there are four other crossovers between what I suppose is the Up Fast (leading to platforms 5-7) and the other ac lines, requiring nine neutral sections, and three or four sections of OHLE to be switched between ac and dc (depending on whether or not platform 7 was included).

 

I think the track plan I have is from the 1970s, but it appears to be the same as this one, at least as far as the dc lines west of Ardwick Junction are concerned: http://raildar.co.uk/map/MAN, My trackplan doesn't have the crossover between platforms 5 and 6, which would require another neutral section.

Edited June 30, 2021 by Jeremy C

[woodenhead]

5 minutes ago, Jeremy C said:

I had always assumed that 1-4 were dc and the rest were ac

 

Looking at the track plan I have, I suppose it would be possible to switch 5-7 (6 came off 7), involving just one crossover between the Ardwick and Longsight lines, but there are four other crossovers between what I suppose is the Up Fast (leading to platforms 5-7) and the other ac lines, requiring nine neutral sections, and three or four sections of OHLE to be switched between ac and dc (depending on whether or not platform 7 was included).

 

I think the track plan I have is from the 1970s, but it appears to be the same as this one, at least as far as the dc lines west of Ardwick Junction are concerned: http://raildar.co.uk/map/MAN, My trackplan doesn't have the crossover between platforms 5 and 6, which would require another neutral section.

That is my understanding too, in the end they only needed two platforms but in the 60s when the station was rebuilt there were still loco hauled trains through to Sheffield.  It would seem extremely complicated to have a dual voltage platform with all the necessary neutral sections to allow such a switchover.

[Michael Hodgson]

48 minutes ago, woodenhead said:

That is my understanding too, in the end they only needed two platforms but in the 60s when the station was rebuilt there were still loco hauled trains through to Sheffield.  It would seem extremely complicated to have a dual voltage platform with all the necessary neutral sections to allow such a switchover.

If changeover of a couple of platforms could occur under signaller control, how would they ensure that it wasn't changed when there was a unit of the wrong type already in ones of the platforms concerned, with its pan up?   

 

I can't see it being safe to rely on Instructions to SIgnalmen alone ("Don't flip that switch or some of the trains will go bang!")

[nigb55009]

According to " Woodhead,  The Electric Railway" (Foxline Publishing), when 25kv was installed, all OHLE masts between Ardwick Junction and Piccadilly station were renewed, including the goods yards to the east of the station. Special instructions were introduced around 1969/70 after an incident involving a DC locomotive. The diesel hauled Harwich boat train failed and was rescued by an electric loco. However, no one told Piccadilly Signallers, who routed the train into it`s usual platform 6. Only platforms 1-4 were DC 1500v. The details of the damage caused are not recorded, although we can probably guess the Drivers reaction. The same situation would have occurred at Oxford Road. The 25kv ran as far as there, where the MSJ&A ran into the bay platforms. Any station overruns would have produced a similar result.

[Zomboid]

Switched sections of OLE do exist, though not in the UK. I believe Aachen has some platforms which can be energised at different voltages, but quite how the control system for that works I've no idea.

[Fat Controller]

1 minute ago, Zomboid said:

Switched sections of OLE do exist, though not in the UK. I believe Aachen has some platforms which can be energised at different voltages, but quite how the control system for that works I've no idea.

Eurotunnel has switchable catenary on the platforms used for HGV traffic; the power is cut during loading and unloading of trains formed of the newer stock, which does not have full length roofs. Train type is recognised by a 'balise' (transponder), which does not allow such trains to be routed into a non-switchable platform.

[Michael Hodgson]

36 minutes ago, nigb55009 said:

The details of the damage caused are not recorded, although we can probably guess the Drivers reaction.

I don't think should have needed a clean pair of underpants - his cab would be a Faraday cage wouldn't it? 

Anyway, the signalling should have told him which platform he was approaching so he ought to have refused the route. 

[Michael Hodgson]

34 minutes ago, Zomboid said:

Switched sections of OLE do exist, though not in the UK. I believe Aachen has some platforms which can be energised at different voltages, but quite how the control system for that works I've no idea.

We have been switching trains from 25kV overhead to third rail DC at Drayton Park for nearly half a century though and Thameslink has been doing it too. Rather easier to control the risks I think.

[Zomboid]

I specifically meant OLE switchable between one voltage and another. On/ Off is a vastly simpler matter, and differently voltages on different conductors with different collectors are much easier too.

[nigb55009]

You`re right about the cab of course, I was referring more to the noise that would have greeted his sudden realisation that he shouldn`t have accepted the route he`d been given.

[The Stationmaster]

1 hour ago, Michael Hodgson said:

I don't think should have needed a clean pair of underpants - his cab would be a Faraday cage wouldn't it? 

Anyway, the signalling should have told him which platform he was approaching so he ought to have refused the route. 

The critical words are 'ought to have' - you might be surprised at the number of passenger trains worked b 3rd rail electric units which turned right at Reading Spur Jcn instead of going straight on - notwithstanding the illuminated JI exhibited by the (approach released) signal.  The Drivers of such miscreant trains then discovered that a unit drawing power from the 3rd rail wouldn't move once it had got onto non-electrified infrastructure  

 

And over the years various Drivers have found out that pantographs not only don't collect power when raised where there are no overhead lines but v can havea nasty habit of colliding with things such as bridges and signal gantries if raised at just the wrong moment.

 

Our European mainland neighbours do seem to do better at doing it correctly most of the time and 'gares commutable' are quite common

[Jeremy Cumberland]

2 hours ago, nigb55009 said:

According to " Woodhead,  The Electric Railway" (Foxline Publishing), when 25kv was installed, all OHLE masts between Ardwick Junction and Piccadilly station were renewed, including the goods yards to the east of the station. Special instructions were introduced around 1969/70 after an incident involving a DC locomotive. The diesel hauled Harwich boat train failed and was rescued by an electric loco. However, no one told Piccadilly Signallers, who routed the train into it`s usual platform 6. Only platforms 1-4 were DC 1500v. The details of the damage caused are not recorded, although we can probably guess the Drivers reaction.

To my mind, this episode supports platform 6 being switchable.

 

It seems inconceivable to me that the signalling would not have told the driver which route was set. If the crossover wasn't wired and platform 6 was ac only, then the driver would be almost certain to stop - how often would an EM1/EM2 driver have used any platforms other than 1-4? The unusual signal indication (however it was displayed) would surely have prompted the driver to react. Or perhaps not, after reading The Stationmaster's post.

 

However, if platform 6 was switchable, then the driver would presumably not have realised that anything was wrong.

[The Stationmaster]

2 hours ago, Zomboid said:

Switched sections of OLE do exist, though not in the UK. I believe Aachen has some platforms which can be energised at different voltages, but quite how the control system for that works I've no idea.

I understand that Aachen is no longer a 'gare commutable' - but there are plenty of others around

 

here's one example (text in French but reasonably self-explanatory I hope -

https://www.youtube.com/watch?v=E4XGl1bt8xg

 

Another method, at passing stations, is used in a different way - quite spectacularly - by multi-current locos on non-stop trains .  They lower the pan as they approach drawing power from one system and then raise the other pan once they are under the other  system.  All done a full line speed with a bit of arcing to add to the amusement for onlookers.

[PenrithBeacon]

4 hours ago, nigb55009 said:

According to " Woodhead,  The Electric Railway" (Foxline Publishing), when 25kv was installed, all OHLE masts between Ardwick Junction and Piccadilly station were renewed, including the goods yards to the east of the station.

...

There are video cab rides which include the section from Piccadilly to Guide Bridge that support this statement.

[Johann Marsbar]

2 hours ago, Jeremy C said:

To my mind, this episode supports platform 6 being switchable.

 

It seems inconceivable to me that the signalling would not have told the driver which route was set. If the crossover wasn't wired and platform 6 was ac only, then the driver would be almost certain to stop - how often would an EM1/EM2 driver have used any platforms other than 1-4? The unusual signal indication (however it was displayed) would surely have prompted the driver to react. Or perhaps not, after reading The Stationmaster's post.

 

However, if platform 6 was switchable, then the driver would presumably not have realised that anything was wrong.

 

Platform 5 was the usual platform at Piccadilly that the Harwich boat train used rather than 6.     I travelled on it enough over the years......

[Michael Hodgson]

3 hours ago, The Stationmaster said:

The critical words are 'ought to have' - you might be surprised at the number of passenger trains worked b 3rd rail electric units which turned right at Reading Spur Jcn instead of going straight on - notwithstanding the illuminated JI exhibited by the (approach released) signal.  The Drivers of such miscreant trains then discovered that a unit drawing power from the 3rd rail wouldn't move once it had got onto non-electrified infrastructure  

 

And over the years various Drivers have found out that pantographs not only don't collect power when raised where there are no overhead lines but v can havea nasty habit of colliding with things such as bridges and signal gantries if raised at just the wrong moment.I

I'm afraid it doesn't surprise me - I've seen too many HGVs hit ECML bridge 102 at Hitchin despite a large height detector triggered sign that suddenly starts flashing yellow lights and an illuminated legend reading "Overheight Vehicle Divert".  It doesn't seem to happen quite as frequently as it used to these days, and I'm not sure why - perhaps more lorry drivers are using satnavs that avoid this route, or perhaps  following Brexit there are now fewer drivers here with very limited English.  Maybe that sign should be flashing the international standard sign for height prohibition.  

 

As for a train driver who takes the signal when it routes him off the overheads, it can take quite a few EMUs coupled together acting as reach wagons to drag him back under the wires again!   

[nexusdj]

There are a few pics on Flickr taken at Ardwick from various photographers showing the crossover between the DC and AC fitted lines and there's a double set of insulators on both the contact and catenary wires . Would of made a mess if a pantograph had tried to run along that section of catenary !

 

Tony Walmsley image taken 1983   : https://www.flickr.com/photos/75514026@N03/23258605816/sizes/h/

 

Note also the additional mesh partition on each of the gantries between the two systems . 

 

Edited June 30, 2021 by nexusdj

[jim.snowdon]

7 hours ago, Jeremy C said:

To my mind, this episode supports platform 6 being switchable.

 

It seems inconceivable to me that the signalling would not have told the driver which route was set. If the crossover wasn't wired and platform 6 was ac only, then the driver would be almost certain to stop - how often would an EM1/EM2 driver have used any platforms other than 1-4? The unusual signal indication (however it was displayed) would surely have prompted the driver to react. Or perhaps not, after reading The Stationmaster's post.

 

However, if platform 6 was switchable, then the driver would presumably not have realised that anything was wrong.

I would have expected that if there were any platforms at Manchester Piccadilly that were switchable between AC and DC it would have merited a mention in the AC Electrified Lines Working Instructions. I have a copy of the July 1960 edition, and no mention is made.

 

[adb968008]

I always understood the DC platforms were uniquely for DC operation, until the class 506s went, never saw AC using those platforms.

[Clive Mortimore]

2 hours ago, nexusdj said:

There are a few pics on Flickr taken at Ardwick from various photographers showing the crossover between the DC and AC fitted lines and there's a double set of insulators on both the contact and catenary wires . Would of made a mess if a pantograph had tried to run along that section of catenary !

 

Tony Walmsley image taken 1983   : https://www.flickr.com/photos/75514026@N03/23258605816/sizes/h/

 

Note also the additional mesh partition on each of the gantries between the two systems . 

 

I think the insulators we are looking at are normal ones for a out of running wire going to a terminating point or tensioning weight.

 

Similar ones at Chelmsford

 

[great central]

Regarding drivers taking the wrong route, it happens, momentary lapse of concentration and you're past the point of no return. It can happen to any of us doing any job, had the odd incident myself but I'm not a driver.

There was one a few weeks ago that I know about although I can't share details, no harm done apart from some inconvenience for passengers and awkward questions for said driver.