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

[PlatformEdgeVT]

I have recorded a Merseyrail train for a YouTube video, but I can't tell whether it is a 508 or 507 (I am not as experienced with Merseyrail). Please could you tell me the differences between the two types or tell me which class it is. I have attached a video of the train, if that helps.View attachment VID_20220724_141500.mp4

 

[TT-ONR-NRN]

One difference, although presumably not the main one, is 508 lighting can’t handle gaps in the third rail and will flicker off when the shoe goes over it, also the compressor can be heard on those and not 507s… not sure of any other difference really

 

[hexagon789]

I have recorded a Merseyrail train for a YouTube video, but I can't tell whether it is a 508 or 507 (I am not as experienced with Merseyrail). Please could you tell me the differences between the two types or tell me which class it is. I have attached a video of the train, if that helps.View attachment 118194

507s were built as 3-car
508s were originally 4-car, reduced to.3 when sent north.

507s have one compressor
508s have two

507s have GEC traction motors
508s have GEC or Brush motors

507s have a more limited voltage range (600-750V)
508s have a theoretically wider range designed to handle the Southern Region 3rd rail (they can tolerate a continuous line voltage of 850V and a higher peak voltage, this being theoretically necessary for the Bournemouth line)

507s have Girling WSP
508s have the BR Mk2 system


There's probably some other things I can't find.

 

[prod_pep]

Just to expand on Hexagon's post, the 507s have one Westinghouse 3HC43 compressor per three car set (under the 644XX carriage) while the 508s have two of the older Westinghouse DH25 compressors per set which run in unison. This is a legacy of the 508s' original life as four coach Southern Region units.

All 508s have GEC traction motors; it is the 314s and 315s of this family which are mixed GEC and Brush.

Prior to the 2002-05 refurbishment, an obvious external difference was the presence of plated-over door controls on the 508s which the 507s, never having had passenger door controls, lacked.

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.

Possibly the brakes on the 508s are by a different manufacturer from the 507s, but I'm not sure on this (the 314s and 315s have dual-sourced brakes).

 

[XAM2175]

There's probably some other things I can't find.

Just to expand on Hexagon's post...

I think the OP is really only interested in having the unit in their video identified, to be honest:

I have recorded a Merseyrail train for a YouTube video, but I can't tell whether it is a 508 or 507. Please could you ... tell me which class it is.

---
EDIT: they got an answer in the TOPS thread.

 

[61653 HTAFC]

I'm assuming the OP was after visual differences, which would assist in identifying which class a unit is when the numbers can't be seen. I'm not aware of any obvious visual differences but that's not to say there aren't some.

 

[hexagon789]

All 508s have GEC traction motors; it is the 314s and 315s of this family which are mixed GEC and Brush.

My apologies, the diagram book says they are mixed GEC or Brush as with tye 314 fleet. I know Wikipedia says this too but I wasn't trusting it, I thought the BR diagram books would be a more reliable source!

 

[Snow1964]

As built the 508s had passenger door controls, later blanked off with small square plates on the outside (about 4 inches square and at tummy height), there was even ones to the side of cab doors, as originally passengers could use the intermediate cabs when operating in multiple.

The 507s had a thin orange warning stripe at the top of the sides, this wasn’t included on the 508s when they were in SW London. However since repainting this livery difference has gone.

 

[prod_pep]

My apologies, the diagram book says they are mixed GEC or Brush as with tye 314 fleet. I know Wikipedia says this too but I wasn't trusting it, I thought the BR diagram books would be a more reliable source!

Yes, I think that's an oversight in the diagram books. Just for anyone interested: with the 314/5 fleets, the GEC and Brush motors can be differentiated by the 'clunk' that only the GEC motors make when power is applied and the slightly lower pitch of the Brush motors.

Pedant hat on here: another mistake on the Wikipedia page is '4PER' given as an alternative name for the 508s. This was actually the originally planned name for the PEP units (i.e. the 445/446), standing for 'Prototype Electro-Rheostatic'.

 

[Mikey C]

I'm assuming the OP was after visual differences, which would assist in identifying which class a unit is when the numbers can't be seen. I'm not aware of any obvious visual differences but that's not to say there aren't some.

In general, aren't all the PEP bodyshells identical? Far more so than the later Mk3 EMUs

 

[61653 HTAFC]

In general, aren't all the PEP bodyshells identical? Far more so than the later Mk3 EMUs

Pretty much so. Might be differences in the equipment mounted beneath the bodyshell which would aid identification though.

 

[507 001]

In general, aren't all the PEP bodyshells identical? Far more so than the later Mk3 EMUs

The trailers had different window arrangements.

 

[PlatformEdgeVT]

I was mostly looking for visual differences, though I have learned quite a bit from this. Thanks! (And yes, @XAM2175 , I was mostly looking to identify the class of the unit, though its full number has been found.)

 

[XAM2175]

Pedant hat on here: another mistake on the Wikipedia page is '4PER' given as an alternative name for the 508s. This was actually the originally planned name for the PEP units (i.e. the 445/446), standing for 'Prototype Electro-Rheostatic'.

That's sourced to Colin Marsden's Motive Power Recognition: EMUs, so that's who made the mistake.

 

[fgwrich]

That's sourced to Colin Marsden's Motive Power Recognition: EMUs, so that's who made the mistake.

Something all too common with that particular Author unfortunately!

 

[hexagon789]

That's sourced to Colin Marsden's Motive Power Recognition: EMUs, so that's who made the mistake.

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

 

[Bletchleyite]

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

508s also used to have blanking plates on the doors themselves where the original PEP physical handles would have gone. They also had blanked off yellow boxes at the sides inside (both sides) where the open buttons went. Half of those were removed and fitted to the 507s, with all of them containing the staff control box, in the 1998ish refurb, but I think they have all been removed and the box moved to the partition in the second refurb.

 

[contrex]

I thought that myth about 850v on the Bournemouth electrification had been put to bed long ago?

 

[prod_pep]

508s also used to have blanking plates on the doors themselves where the original PEP physical handles would have gone. They also had blanked off yellow boxes at the sides inside (both sides) where the open buttons went. Half of those were removed and fitted to the 507s, with all of them containing the staff control box, in the 1998ish refurb, but I think they have all been removed and the box moved to the partition in the second refurb.

They actually fitted new control boxes to the 507s rather than robbing them from 508s as I recall, this process being carried out after they had finished the 1992-97 refreshment programme. The 508s retained a plated-over set of door controls on the right side of each door bay until refurbishment from 2002 saw them removed.

 

[Bletchleyite]

They actually fitted new control boxes to the 507s rather than robbing them from 508s as I recall, this process being carried out after they had finished the 1992-97 refreshment programme. The 508s retained a plated-over set of door controls on the right side of each door bay until refurbishment from 2002 saw them removed.

They may have removed half of the 508 ones and thrown them in the bin, but as built 508s definitely had the blanked off boxes on both sides, but post that refurb only one side with the staff control box.

 

[prod_pep]

They may have removed half of the 508 ones and thrown them in the bin, but as built 508s definitely had the blanked off boxes on both sides, but post that refurb only one side with the staff control box.

Sorry for the pedantry again but allow me to clarify. As built, the 508s had internal passenger door controls both sides of each door set, which were blanked off with yellow panels when they transferred to Liverpool. What I'm saying is they did not remove any of these when both the 507s and 508s were fitted with guard controls at each door set around 1999. The 507s received a completely new box and the 508s had their left side panel modified into a guard control box, with the right side ones staying blanked over - not removed. This remained the case until the 2002-05 replacement.

Below is an example of what I mean: an unrefurbished 508 interior photo from summer 2004. On the left is a plated over set of door controls and on the right is a set converted to a guard's panel.

 

[XAM2175]

Something all too common with that particular Author unfortunately!

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

I don't suppose you can point out a reputable source refuting Mr Marsden's error, so we can get it fixed?

 

[Bletchleyite]

Sorry for the pedantry again but allow me to clarify. As built, the 508s had internal passenger door controls both sides of each door set, which were blanked off with yellow panels when they transferred to Liverpool. What I'm saying is they did not remove any of these when both the 507s and 508s were fitted with guard controls at each door set around 1999. The 507s received a completely new box and the 508s had their left side panel modified into a guard control box, with the right side ones staying blanked over - not removed. This remained the case until the 2002-05 replacement.

Below is an example of what I mean: an unrefurbished 508 interior photo from summer 2004. On the left is a plated over set of door controls and on the right is a set converted to a guard's panel.

Thanks - I stand corrected! A nostalgic pic too

 

[hexagon789]

I thought that myth about 850v on the Bournemouth electrification had been put to bed long ago?

The nominal voltage was 750V, but the peak was 850V hence the traction equipment needing to tolerate at least 850V. The line from Waterloo to Surbiton was still at 660V nominal (750V peak) when the Bournemouth electrification was completed, the line voltage went up in 4 stages to the full 750V beyond there. (This is taken from an issue of The Railway Magazine of the period).

Perhaps I didn't word my precise meaning very well above.

I don't suppose you can point out a reputable source refuting Mr Marsden's error, so we can get it fixed?

Unless there's an official paper with the relevant designations I suspect that might be difficult.

 

[XAM2175]

Unless there's an official paper with the relevant designations I suspect that might be difficult.

Something discrediting Mr Marsden's publications en bloc would also do nicely

 

[northernbelle]

Something all too common with that particular Author unfortunately!

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

Something discrediting Mr Marsden's publications en bloc would also do nicely

And how many books and magazines have you had published?

I don't really see the need for you to be so personal when the chap has undoubtedly make a huge contribution in recording the modern railway scene over many years.

 

[contrex]

The nominal voltage was 750V, but the peak was 850V

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.

 

[hexagon789]

I read somewhere that the voltage for timing purposes is 670V.

I don't know about that, all I remember reading in a Practice & Performance was that the Southern didn't use inserted sections pf recovery time instead they added a performance margin of 5% or something like that to the sectional running times.

I believe the 1959-62 Kent Coast scheme was 750 nominal from the start.

That's my understanding as well.

 

[fgwrich]

Something discrediting Mr Marsden's publications en bloc would also do nicely

And how many books and magazines have you had published?

I don't really see the need for you to be so personal when the chap has undoubtedly make a huge contribution in recording the modern railway scene over many years.

I would also like to ask the same for you then? Without trying to digress this thread further, his recent "Ultimate Definitive Guide to the HST" is another example ridden with silly errors and some re-writing of recent history, including suggesting the Midland Mainline "Ocean Blue" livery was planned and implemented by Stagecoach, there are also errors regarding his Power Car fleet lists, and errors regarding the captioning and labelling of BR Mk3 Diagrams - a lot of this can easily be avoidable, but Mr Marsden seems to chose to present his opinion as definitive facts - despite having been pointed out to him on numerous occasions before. While I don't have any publications myself, both my father does and I have also had numerous photos published in a much more factual HST Guide last year. I don't doubt he has had a presence over the last few decades, but books / guides and websites full of avoidable errors does starts to somewhat wear after a while. And yes, I've also had it where I've provided a caption for one of my photos to him, only for the caption to be disregarded and an error strewn one put up in it's place.

Anyway, going back to the 507s and 508s - I wonder which vehicles will last longer, the Ex South Western 508s working up on Merseyside, or the ex 508 vehicles working in 455s still on the South Western.

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!

 

[northernbelle]

I would also like to ask the same for you then? Without trying to digress this thread further, his recent "Ultimate Definitive Guide to the HST" is another example ridden with silly errors and some re-writing of recent history, including suggesting the Midland Mainline "Ocean Blue" livery was planned and implemented by Stagecoach, there are also errors regarding his Power Car fleet lists, and errors regarding the captioning and labelling of BR Mk3 Diagrams - a lot of this can easily be avoidable, but Mr Marsden seems to chose to present his opinion as definitive facts - despite having been pointed out to him on numerous occasions before. While I don't have any publications myself, both my father does and I have also had numerous photos published in a much more factual HST Guide last year. I don't doubt he has had a presence over the last few decades, but books / guides and websites full of avoidable errors does starts to somewhat wear after a while. And yes, I've also had it where I've provided a caption for one of my photos to him, only for the caption to be disregarded and an error strewn one put up in it's place.

Anyway, going back to the 507s and 508s - I wonder which vehicles will last longer, the Ex South Western 508s working up on Merseyside, or the ex 508 vehicles working in 455s still on the South Western.

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!

Just a little kindness is all I was requesting