What are the differences between Class 507s and 508s?

[Bow Fell]

The issue with gaps causing lights to flicker off on 508s is intermittent and doesn't seem to affect all examples, and again this only happened following the reduction to three carriages.

It will happen to all 508’s, it’s a design feature. The lighting is directly fed from the MA set. On 507’s the lighting is fed from the batteries.

 

[D365]

It will happen to all 508’s, it’s a design feature. The lighting is directly fed from the MA set. On 507’s the lighting is fed from the batteries.

Interesting. So there’s definitely a difference in the electrical arrangements.

 

[Bletchleyite]

Also - wow @prod_pep , That MerseyRail interior photo is a throwback. I still feel that the transformation of these units by Alstom really was one of the best refurbishments of the decade, even now they certainly don't look 40 years of age!

Some of my family were certainly fooled. Though they've suffered a bit from the general British "lack of maintenance" malaise and have got a bit scruffy, just like the whole of Merseyrail really.

 

[pdeaves]

Some of my family were certainly fooled. Though they've suffered a bit from the general British "lack of maintenance" malaise and have got a bit scruffy, just like the whole of Merseyrail really.

I trust your second sentence refers to the trains, not your family

Visibly, the 507s and 508s are essentially identical (where there are differences, you have to know what to look for underneath), yes?

 

[nlogax]

A Colin Marsden production making a mistake? Now there's a surprise...

Think I made exactly the same error on here a couple of years back on a PEP thread..relied on my copy of the exact same book. Encouraging to know it's not just me

 

[johnw]

Where the 508s originally ordered for Merseyside then diverted to the Southern region?

 

[315801]

Where the 508s originally ordered for Merseyside then diverted to the Southern region?

Hi johnw:

You are quite correct, the 508s were as you said originally intended to end up here in the wirral although I am not sure whether they had already been built as 3 or 4 coach sets at that time and because the southern were getting rid of the stock that the 508s replaced, they were used down there for a few years until the 455s started to be delivered.

Once there was a sufficient number of 455 units delivered, the 508s started to be reduced from 4 to 3 coaches and the extra trailer coaches were added into some of the 455s which were classed as 455/7. These units are easily identified by looking at the roof profile because 3 coaches of a 455/7 unit have the rounded roof and the 4th coach being the former 508 coach has a flat roof and sloping coach sides whereas the other 3 coaches have straight vertical coach sides.

I have to admit here that had the 508s been delivered to the wirral as 4 coach sets from the start, we would have had 43 units with more seating capacity, therefore meaning that even though coupling the units for passenger service would not have been possible due to our restricted platform lengths and the prohibitive cost of lengthening the the underground platforms to accommodate 8 coaches.

As a result of this, the decision was taken by merseyrail to have the 508s reduced to 3 coaches therefore giving a 6 coach formation in peak times.

 

[Skie]

Re the lights, I recall some 508s don't have a busbar connecting the power coaches but all 507s do?

There was a cabride video that the driver or TI mentioned this in:

 

[Bletchleyite]

There's a small plate on the shoebeam that says something like "through bus bar fitted - shoe gear live from other motor coach" on those that do have them. Never looked to see if that plate was present on all of them.

 

[315801]

I can confirm that all the 507 & 508 units have through busbar fitted shoe gear alive from the other motor coach as the 2 driving coaches only have shoe gear on the inner bogies only.

The reason the shoes were removed from the cab end bogies was because when the shoes entered a gap at a crossing or ran over the 3rd rail on the outer side of turnouts ( ie the left hand side of the track if looking out from the cab window ) the shoes would strike an arc which caused the units to jerk and 507001 which the video shown in post #38 was at the time of filming the only unit fitted with the through busbar as a trial to see if the ride quality was improved when running through crossings and turnouts.

After several months of testing, all the units were set up in this format and still run with this shoe gear set up.

 

[507 001]

The one thing that I’ve never been able to figure out, and it is probably just a quirk of TOPS, is why the 508s weren’t just classed as 507/1?

 

[Bletchleyite]

The one thing that I’ve never been able to figure out, and it is probably just a quirk of TOPS, is why the 508s weren’t just classed as 507/1?

You could ask the same question of why the 80x aren't just 800/0, /2, /5 and /7 rather than 800, 802, 805 and 807. Only the 24m MML units are really different enough for a whole class number.

The answer in both cases is probably just "it's a bit arbitrary", alongside "there's tons of space in the 5xx range because there are hardly any non South East third rail EMUs".

 

[507 001]

You could ask the same question of why the 80x aren't just 800/0, /2, /5 and /7 rather than 800, 802, 805 and 807. Only the 24m MML units are really different enough for a whole class number.

The answer in both cases is probably just "it's a bit arbitrary", alongside "there's tons of space in the 5xx range because there are hardly any non South East third rail EMUs".

Well indeed, hence why I think it’s just a quirk of TOPS.

 

[Skie]

It may hark back to the previous classes being 502/503. Whilst there were greater differences between those units, they were also used for different workings on the Wirral and Liverpool sides. This was apparently the intent early on with the pep fleet but that plan never really took hold and they were mixed up early on.

 

[D365]

You could ask the same question of why the 80x aren't just 800/0, /2, /5 and /7 rather than 800, 802, 805 and 807. Only the 24m MML units are really different enough for a whole class number.

The answer in both cases is probably just "it's a bit arbitrary", alongside "there's tons of space in the 5xx range because there are hardly any non South East third rail EMUs".

There are enough incremental differences between each AT300 implementation to warrant a new TOPS designation. Plus it makes it easier for those in the industry to distinguish between fleets.

 

[33109]

Sure I've read somewhere that there used to be sub classes of 508/2 & 508/3. Can't think what for mind you.

Also there was rumour floating about that either the 507s or 508s are going through life extension works?

Presume that's to do with the palava of getting the 777 fleet ready or is there another reason.

 

[Bletchleyite]

Sure I've read somewhere that there used to be sub classes of 508/2 & 508/3. Can't think what for mind you.

Also there was rumour floating about that either the 507s or 508s are going through life extension works?

Presume that's to do with the palava of getting the 777 fleet ready or is there another reason.

In my understanding some 50x (not sure which) are going to be retained for peak Southport line 6-car work until the platform/signalling work is done to allow for 8-car working at Southport. I suspect on the other lines, if affected*, which are generally a bit quieter, they'll be able to get away with not running double sets at all, as a 4-car 777 has quite a bit more capacity (albeit mostly standing) than a 50x.

* I seem to recall the starting signal at Ormskirk is very close to the end of a 6-car so it probably needs work too, unless it's possible to solve it by moving the stopping position nearer the buffers.

 

[bramling]

Sure I've read somewhere that there used to be sub classes of 508/2 & 508/3. Can't think what for mind you.

Also there was rumour floating about that either the 507s or 508s are going through life extension works?

Presume that's to do with the palava of getting the 777 fleet ready or is there another reason.

Those numbered in the 2xx range were the Connex units, and those in the 3xx the three units used for a time by Silverlink. All now history of course.

 

[gka472l]

Sure I've read somewhere that there used to be sub classes of 508/2 & 508/3. Can't think what for mind you.

Also there was rumour floating about that either the 507s or 508s are going through life extension works?

Presume that's to do with the palava of getting the 777 fleet ready or is there another reason.

508/2 were 508201-508212 which were previously surplus Merseyrail units and used by Connex in Kent, 508/3 were 508301-508303, also surplus Merseyrail units, used by Silverlink on Euston/Watford DC lines.

Here's the 508/2 & 508/3 with the previous Merseyrail numbers

508201 (508101)
508202 (508105)
508203 (508106)
508204 (508107)
508205 (508109)
508206 (508113)
508207 (508116)
508208 (508119)
508209 (508121)
508210 (508129)
508211 (508132)
508212 (508133)

508301 (508102)
508302 (508135)
508303 (508142)

All 508/2 & 508/3 scrapped as far as I know with the exception of a car each from 508201 & 508209 in Merseyside for emergency services training (located at Seacombe) and the two driving cars from 508207 which are the Arlington translator coaches.

HTH

 

[prod_pep]

This has been mentioned before: the designation Class 508 may have been intended for Merseyside, but the sets themselves were built as four carriage for the Southern Region, including different compressors, door controls and the other differences we've already pointed out making the 508s different enough to justify their own class designation. The fact 58 units were planned suggests the decision to use them on the SR was made early on, as nothing like that number would ever be required on Merseyside. The 455s were originally to be Class 510 as well, I think, despite the 5XX designation being mainly used for non-SR third rail stock.

Once the 508s had been delivered to Wimbledon, it wasn't a certainty they would actually be cascaded to Liverpool. There was a degree of negotiation between British Rail and Merseyside PTE once the 455s had been ordered before the transfer was agreed. The first 508s to be transferred were for the Northern Line to bolster the 507 fleet in early 1982, with the first 508s not used on the Wirral Line until 1984.

As for the 508/2s, 508212 also still exists at the Fire Service Training College, Moreton-in-Marsh, albeit in a very sorry state now: https://flickr.com/photos/truebritishmetal/52031283680/in/album-72177720298394651/ (Photo copyright True British Metal)

 

[Taunton]

I read somewhere that the voltage for timing purposes is 670V. As with any power supply, I imagine the substation bus bar voltage off load could rise somewhat. I believe the idea that the nominal was 850 was encouraged by sloppy journalism and is still around in some quarters. I believe the 1959-62 Kent Coast scheme was 750 nominal from the start.

This has come up here more than once before. The Modern Railways articles published in 1967, at the time of the electrification, and clearly just taken from BR engineering staff (if not actually written by them), straightforwardly stated that the voltage west of Pirbright Junction was 850v, though not whether this was nominal or maximum. It went on to describe how SR-era units like 4-SUBs could now get to Eastleigh works under their own power rather than being hauled, but some precautions had to be taken, both heating and lighting had to be off, etc, as certain elements were not rated for the higher voltage.

Of course, things could have changed since 1967. Or it could be that the accounts on this board of it not being a higher voltage than the suburban area are an urban legend here in themselves.

 

[Peter Mugridge]

The 455s were originally to be Class 510 as well, I think, despite the 5XX designation being mainly used for non-SR third rail stock.

They were, and many of the early 455/8s carried stickers inside the cabs labelled thus - although that's probably a subject for another thread!

 

[contrex]

This has come up here more than once before. The Modern Railways articles published in 1967, at the time of the electrification, and clearly just taken from BR engineering staff (if not actually written by them), straightforwardly stated that the voltage west of Pirbright Junction was 850v, though not whether this was nominal or maximum. It went on to describe how SR-era units like 4-SUBs could now get to Eastleigh works under their own power rather than being hauled, but some precautions had to be taken, both heating and lighting had to be off, etc, as certain elements were not rated for the higher voltage.

Of course, things could have changed since 1967. Or it could be that the accounts on this board of it not being a higher voltage than the suburban area are an urban legend here in themselves.

That MR article has a lot to answer for. The "850 volts west of Pirbright Junction" notion is a myth. A (then) Network Rail engineer, Richard Catlow, nailed that on the uk.railway Usenet group years ago. The Kent Coast and Bournemouth electrifications were nominally 750V, although (of course) the off-load voltage at the substation busbars could be somewhat higher. For reasons mainly to do with interfaces to LUL lines, the voltage in the inner area were raised gradually from 650 as you got further out. Later on other lines were upgraded to 750V. On the Brighton line the 750v started south of Stoats Nest. Now that the SSL lines are 750v, this isn't necessary, and I believe that eventually the whole Southern region network is being upgraded to 750v.

 

[L401CJF]

Sure I've read somewhere that there used to be sub classes of 508/2 & 508/3. Can't think what for mind you.

Also there was rumour floating about that either the 507s or 508s are going through life extension works?

Presume that's to do with the palava of getting the 777 fleet ready or is there another reason.

If I remember rightly the 508/3s with Silverlink had some mods to allow them to work in multiple with 313/1s on DC lines? Although my mind could be playing tricks on me!

 

[prod_pep]

If I remember rightly the 508/3s with Silverlink had some mods to allow them to work in multiple with 313/1s on DC lines? Although my mind could be playing tricks on me!

That's right but only for ECS moves. 313s were needed to haul the 508s onto the AC wired Willesden Depot.

Silverlink generally did not use its 313s and 508s in multiple in service. Most routes had short platforms and the Euston - Watford route had current issues when 6 cars were used. The only exception I think was when the 321s were sidelined in September 2003 and a stopping London Euston - Milton Keynes Central service was provided by 6 car 313s (including some WAGN examples on loan).

 

[boiledbeans2]

A lot of informative technical details in this thread!

Slightly off topic, but what are the differences between a 313 and 507, besides the 313 having a pantograph?

 

[L401CJF]

A lot of informative technical details in this thread!

Slightly off topic, but what are the differences between a 313 and 507, besides the 313 having a pantograph?

I couple I know of are different compressors and also the pneumatic camshaft equipment is set up slightly differently. On a 313 the air is released from the system when the camshaft is notching up (hence the psh psh psh) noises.

On a 507/8 the air stays in the system so you can only hear and feel a very quiet click for each of the notches.

 

[61653 HTAFC]

A lot of informative technical details in this thread!

Slightly off topic, but what are the differences between a 313 and 507, besides the 313 having a pantograph?

I couple I know of are different compressors and also the pneumatic camshaft equipment is set up slightly differently. On a 313 the air is released from the system when the camshaft is notching up (hence the psh psh psh) noises.

On a 507/8 the air stays in the system so you can only hear and feel a very quiet click for each of the notches.

One notable visual difference is that the additional electrical equipment required for dual voltage capability (below where the pan is/was) impinges on the interior space of the saloon. This also means the windows are different in this area, whereas the rest of the PEP-derived fleet (314, 315, 507, 508) are/were fairly uniform.

 

[33109]

This has been mentioned before: the designation Class 508 may have been intended for Merseyside, but the sets themselves were built as four carriage for the Southern Region, including different compressors, door controls and the other differences we've already pointed out making the 508s different enough to justify their own class designation. The fact 58 units were planned suggests the decision to use them on the SR was made early on, as nothing like that number would ever be required on Merseyside. The 455s were originally to be Class 510 as well, I think, despite the 5XX designation being mainly used for non-SR third rail stock.

Once the 508s had been delivered to Wimbledon, it wasn't a certainty they would actually be cascaded to Liverpool. There was a degree of negotiation between British Rail and Merseyside PTE once the 455s had been ordered before the transfer was agreed. The first 508s to be transferred were for the Northern Line to bolster the 507 fleet in early 1982, with the first 508s not used on the Wirral Line until 1984.

As for the 508/2s, 508212 also still exists at the Fire Service Training College, Moreton-in-Marsh, albeit in a very sorry state now: https://flickr.com/photos/truebritishmetal/52031283680/in/album-72177720298394651/ (Photo copyright True British Metal)

With that driving car from 508212 the interior looks surprisingly reasonably intact.


Maybe 1 day someone might approach the fire service & preserve it.

 

[D365]

Maybe 1 day someone might approach the fire service & preserve it.

If there was any desire to preserve a PEP-derived unit, it would be now or never.