Alsager

[Starmill]

So I used Alsager the other day, I wanted to go to Crewe - and what a lovely little station it is! Very quaint with the flower beds and everything A little surprising that it's managed by EMT but I can sort of see why. Anyway I was waiting in the shelter on the Crewe bound platform and took a picture see attached. I then realised that the train wasn't coming much further up than that because there was a signal there! The crossing barriers had gone down though. Anyway perhaps in anticipation of this, the guard was at the front and when I jogged up the driver had his head out of the window and said to me "We've got to stop up here because of that signal - if there's a problem we'll be blocking the road for too long." I laughed and said I should have noticed the signal in the picture and got on.

So what's the deal with the signalling for the level crossing at Alsager then? And what happens to Down LM trains which are 4 coaches and wouldn't fit behind that signal in the platform?

Cheers.

 

[Jay247uk]

Alsager was my local station

The LM 4 Car 350s do fit in the platform in front of the signal, just.

Unsure as to why it is signalled this way though

Could do with a sign on the platforms advising people to move down though!

 

[Tomnick]

No doubt the signal is a fair distance back from the crossing to provide sufficient overrun to allow trains to approach with the barriers up. Trains will take a bit longer under those circumstances than a clear run though, which is perhaps why the barriers are now lowered in plenty of time anyway. Indeed, I've been told that this is why the Derby - Crewe trains were changed from class 2 to class 1 - apparently that affects how they're dealt with at Alsager?! Sounds nonsensical to me, but I could still believe it...

 

[LowLevel]

I know there's significant problems with adhesion at Alsager, I don't know if that has anything to do with the signals being located further back from the crossing?

 

[edwin_m]

Attenborough also has a crossing (CCTV) at the platform end, with access to the platform up the end ramp from the crossing road, and a signal midway along the platform.

Not sure what happens there now but when I was a commuter (up to 2006, so before re-signalling) a stopping train to Derby would normally approach with the barriers down and the signal off, and stop near the crossing end of the platform. However if the signal was red, due to the crossing not being closed or any other reason, the train would obviously have to stop before the signal.

I see from National Rail that the access to the Alsager platforms is also up the ramp from the crossing road, so it seems things are done differently here.

 

[Starmill]

Hmmm, interesting stuff! Can 4 coaches really fit behind that signal? Wow.

 

[Jay247uk]

Sorry for the bad picture - taken from my iPhone! There's quite a long stretch of platform behind the signal for the 350s!

 

[Baxenden Bank]

No doubt the signal is a fair distance back from the crossing to provide sufficient overrun to allow trains to approach with the barriers up. Trains will take a bit longer under those circumstances than a clear run though, which is perhaps why the barriers are now lowered in plenty of time anyway. Indeed, I've been told that this is why the Derby - Crewe trains were changed from class 2 to class 1 - apparently that affects how they're dealt with at Alsager?! Sounds nonsensical to me, but I could still believe it...

I like the idea of a single car 153 being a class 1 train - thus having the same status as an 11 car Pendolino!

I have no inside knowledge of why this is so but assumed it was to ensure it got proper priority throughout the route. The service uses busy sections of line with flat crossing movements onto the WCML at Stoke and Kidsgrove, then there is a single track section between Alsager and Crewe. Regularly, if the train arrives at Stoke (from Derby) a bit late, then it is terminated there - rather than trying to shoehorn it down the mainline to Kidsgrove and down the single line section (when the LM Crewe to London service is timed to come in the opposite direction). The LM service being equally difficult to path throughout its journey to Euston.

The Derby - Crewe line has 'community' status with a partnership officer and lots of volunteers looking after all the intermediate stations - hence the good work at Alsager. Nice mural on the waiting shelter too.

 

[Tomnick]

It does lose the effect somewhat when just about every passenger train it'll encounter I along the route is also a class 1! Regulation goes much deeper than that anyway, especially given the push to keep freight running right time too. I've run a class 6 freight on a very tight margin in front of a class 1 recently (normally needs a 15' margin really), because the passenger had a chunk of pathing allowance amounting to 8' over its next ten miles. Similarly, given the choice of putting a couple of minutes into the Crewe train (acknowledging the risk of stuffing the single line, though I don't think there's often anything to come the other way immediately after, and the short turnaround at Crewe) or delaying an Up passenger heading for a tight path south of Colwich, or even the Down local needing to fit in north of Cheadle Hulme, or a class 4 that's running well but might end up being put away somewhere if it picks up a slight delay approaching one of the aforementioned - I think the Crewe train would lose out most times, class 1 or not!

And I still don't understand how it makes any difference to the method of working at Alsager.

 

[Kneedown]

The Drivers of Crewe bound services stopping at Alsager are required to stop before the signal halfway down the platform, even if it is cleared (You can always tell who is and isn't a regular traveller from here based on whether or not they have to make a last minute dash down the platform!)
The reason for this, I was always told, is that if you pass the signal, the dectection tells the Crewe Signaller to lower the barriers at Radway Green level crossing further down the line before Barthomley Junction. With a stopping train at Alsager the barriers would be down there for an excessively long time.
Why it was set up like this, and why it hasn't been modified is for someone with more Signalling technology knowhow than me.

 

[edwin_m]

I'm assuming Radway Green is an AHB so it is activated automatically - if it was manual the signalers could start the sequence later for a stopping train and (as far as I could see) there would be no problem.

If so then the distance from the strike-in point to the crossing (probably in fact the "second train coming" strike-in) is determined by the permitted speed and the minimum warning time required for the lights and barriers. If this location falls part way down the platform at Alsager then a lower speed restriction might be required to move it back towards the crossing. Sometimes a control is provided to hold the signal at danger and inhibit the barrier sequence for a stopping train, as at Bradford-on-Avon for example, but this would result in the train stopping on the approach side of the signal anyway!

 

[Tomnick]

Radway Green is a CCTV crossing, so there shouldn't be a problem with waiting until the train is actually observed to depart from Alsager before starting the sequence. In reality, though, there could well be an annunciator provided to advise the signalman when the train occupies the TC immediately in advance of the signal, they might use the train description stepping as a cue to get on with it or it might just be compliance with the box instructions - in any case, deviating from that carries the risk of failing to observe the train departing from Alsager and forgetting all about Radway Green!

 

[Kneedown]

Tomnick is correct in that Radway Green is a CCTV crossing. Remember that it is controlled by the Signalman at Crewe and so, depending on where the track circuit/axle counter is situated he would not know exactly when the train departed from Alsager.
Nowadays, as has been mentioned before, the Crewe services are class 1 trains. The effect of this is that trains will normally arrive at Alsager on a green signal, as opposed to a red when they were class 2, so the problem of the barriers being lowered too soon at Radway Green has obviously been brushed aside. The regulation of stopping at the signal is still in place though and i'm sure there is still a reason for it. It is certainly good practice for a Driver to stop before the signal at a station whatever the aspect shown unless operational requirements or local instructions dictate otherwise. It's a chance for the Signaller to replace the signal to danger in time should an emergency occur further up the line. There may be a delay if the signal returns to danger when the first wheel passes it and the Guard is staring at the red waiting for it to clear before he despatches the service.

 

[Tomnick]

I still don't understand the distinction between class 1 and 2 trains though - Radway Green shouldn't come into it as long as the train doesn't pass the signal at Alsager if it's already cleared when it arrives. Surely a train stopping at Alsager is a train stopping at Alsager, whether it's class 1, 2 or even something else?!

 

[Kneedown]

I still don't understand the distinction between class 1 and 2 trains though - Radway Green shouldn't come into it as long as the train doesn't pass the signal at Alsager if it's already cleared when it arrives. Surely a train stopping at Alsager is a train stopping at Alsager, whether it's class 1, 2 or even something else?!

As far as a Driver is concerned, Class 1 is express passenger under normal circumstances, Class 2 a stopping or local service.
With regards to difference in signalling the two class's at Alsager, it's something to do with the signalling system in use at Crewe, and someone with more knowledge of this system than me would be better placed to answer as I, unfortunately, havn't a clue how it works.

 

[Tomnick]

I'm just completely perplexed - all I can think is that the crossing at Alsager is provided with an auto-lower facility, with a primitive system to differentiate between trains stopping at Alsager (probably all class 2 at the time!) and those not (probably all others at the time) to give the latter a clear run but not the former. That seems rather convoluted and unlikely though! I'd be surprised if the box instructions differentiated between 1s and 2s - when both are equally capable of being booked to stop or not stop at a given station!