Talk:British Rail Class 508/Archives/2024/June

507/508

Apart from the fact that the 508s were originally in four-car sets, can anybody please clarify what distinguishes the 507 from the 508? Now that the latter are in three-car sets, is there a good reason why they're not reclassified to all be the same class? The articles don't appear to list any other technical difference such as voltage etc. (I don't know the rules for reclassification, but precedent seems to perhaps exist with the 375/377 classes, where 375s were renumbered after the couplers were changed.) – Kieran T ^(talk) 13:06, 15 August 2008 (UTC)

That's not a question I think you will find an answer to on the talk page, though there's potential to make a section or at least paragraph on this. Wikipedia obviously does not decide how trains are classified, and there is a lot of different history between the two trains that means there is no point in merging them into one article. ChillyDude153198 (talk) 17:03, 14 June 2024 (UTC)

Developed for Merseyside? Really?

Do we have a source for this? There's a discussion on the uk.railway Usenet group at the moment which doubts our explanation. Quote:

No they were built new for SR, that was where they were always intended to go when new.

Southern Region just did not like the complexity of 8 motors and two motor coaches and (to them) non standard equipment c.f. single motor coach with 4 x EE507 standardised for all EMU since 1963.

The 500 EMU series is what confuses: the orginal use was ex-LMS / LMR specfici DC EMU *and* then added BR universal DC EMU built to a design for all regions. I think that gen is found in a contemporary RCTS RO.

510/512 were also assigned to SR - DC only 317-types pencilled in for various projects - none using SR standard kit - but one was the 75 mph version before 455 plan (i.e. before the SR CM&EE influcenced it), the other was 100 mph - one of the options considered for Rep replacements - and way before 442 were thought of.

And further down that same discussion:

I've read so many versions of the story - all written way after the event.

IIRC in real time events were something like definitely ordered for SR and intended as the new SR suburban EMU for all future builds from that time. But even before 508 delivery it had already been decided they would move on to LMR; thus they were perceived by many and hence written into myth they were only ever temporary. And wiki has a lot of myths.

Part of the problem really comes down to SR CM&EE continuing to reject BRB standards; they didn't like the PEP, they didn't like the 455, and so on. Set back SR suburban EMU development a decade.

Both quotes are from a pseudonymous contributor who writes under the name "D7666", so is clearly no use as a source for us, but does seem to know what s/he is talking about. D7666's explanation doesn't fit with ours. Either way, we really need sources and citations (we currently have one, and that for a specific incident!) for this page. 86.132.139.119 (talk) 15:13, 23 October 2008 (UTC)

I have no clue if necroposting is a problem on wikipedia, sorry I'm relatively new. Either way, the IP that this comment was posted under is most likely dead now - I'd be very surprised if not!

https://www.railsistem.com/blog/2020/03/18/from-the-archive-first-batch-of-class-508-electric-multiple-units-in-service/ This seems to answer the question ChillyDude153198 (talk) 03:48, 6 May 2024 (UTC)

To add to the discussion, some of the items specified for the Class 508 when built suggest it was not originally meant for Merseyside:

• 508s were built as four car sets. The Merseyrail system has long been designed around trains that are about 60m long (3 cars), with platforms about 120m long.
• The two air compressors on the Class 508 are Westinghouse CM38s, which are a very old type. I believe this was to standardise with other Southern fleets. The Class 507s use a more modern 3HC55 and only need one.
• The lighting on the Class 508 was run directly off the AC output of the MA through ‘conventional’ ballast units. This meant that when the train traversed a third rail gap, the lights would go out. The class 508s had a 750V busline, so gapping the unit was unusual. When built, the Class 507 was not allowed to have a traction busline, so the lights were supplied from the batteries using more expensive lighting inverters. When the 508s moved up to Merseyrail, the busline was significantly shortened. The legacy was the characteristic lighting failure when traversing some points and level crossings, seen only on the 508s.
• Numerous other smaller detail changes. Some were to remove the Southern’s attempts at simplification, for example putting in the load-weighted acceleration control as fitted to the 507 and most other units since. Others were to make the train suitable for Merseyrail, for example removal of the door open pushbuttons. The 750V shore supply was changed to match that fitted to the Class 507 and the Merseyrail depots.

As an additional thought, the Merseyrail Class 508 fleet was reduced by more than 16 units in the mid 1990s. (some units were returned to Merseyrail traffic after the 2002 refurbishment). This could suggest that the number sent up from the Southern was not really what was needed. However, it may also have more to do with passenger traffic and the economy of the Merseyside region at the time. Data Gronk (talk) 06:46, 22 June 2024 (UTC)