Merseyrail Class 507/508

[185143]

What is the difference between the two classes?

 

[455driver]

The 507s were built as 3 coach sets for MerseyRail and the 508s were built as 4 coach sets for the Southern region, then the 455/8xx series were built followed by the 455/7xx series, as the 455/7s were built the 508s were transferred to MerseyRail with one coach being inserted into the 455/7s as they were delivered.

So basically-
3 coach 455/7 built, coach removed from 508 and inserted into 455/7, 508 (now 3 coaches) hauled up to MerseyRail.

 

[8J]

Like 455driver said, the 508's were initially designed to be 4 car units. They do have different compressors because of this. The 508 uses 2 older style compressors where as the 507's use one compressor that is slightly more modern, but not capable of supplying 4 cars with air.

Also, the lighting circuit is designed differently. I'm not sure of the ins and outs of it, but basically, the lights go out when the train is not recieving DC power from the 3rd rail on the 508's where as they are powered differently on the older 507's, so therefore don't go out.

One final difference is the design and layout of the cab. Other than that, pretty much identical. Same GE traction motors, same body shell.

 

[507 001]

Like 455driver said, the 508's were initially designed to be 4 car units. They do have different compressors because of this. The 508 uses 2 older style compressors where as the 507's use one compressor that is slightly more modern, but not capable of supplying 4 cars with air.

Also, the lighting circuit is designed differently. I'm not sure of the ins and outs of it, but basically, the lights go out when the train is not recieving DC power from the 3rd rail on the 508's where as they are powered differently on the older 507's, so therefore don't go out.

One final difference is the design and layout of the cab. Other than that, pretty much identical. Same GE traction motors, same body shell.

The 508s have one newer style compressor and one older style compressor (located in the TOS)
The cabs are the same apart from the speedo and brake gauge.
They also have slightly different WSP systems.

 

[prod_pep]

The 508s have one newer style compressor and one older style compressor (located in the TOS)

Both 508 compressors are identical. They make the 'chugging' noise as opposed to the 'buzz' the single 507 compressor makes.

 

[ScotGG]

Why were the 508s withdrawn from Southeastern? They were in decent condition I believe until withdrawal then left to rot. They were replaced by class 466 which would have been better used attached to very busy (crush loaded) class 465 units. The 4 car services from Victoria to Dartford could have benefitted for example, as could many others.

 

[507 001]

Both 508 compressors are identical. They make the 'chugging' noise as opposed to the 'buzz' the single 507 compressor makes.

Thats not what a Merseyrail DM once told me!

 

[tom1649]

Why were the 508s withdrawn from Southeastern? They were in decent condition I believe until withdrawal then left to rot. They were replaced by class 466 which would have been better used attached to very busy (crush loaded) class 465 units. The 4 car services from Victoria to Dartford could have benefitted for example, as could many others.

I heard differently. Apparently Southeastern ran them into the ground with minimal care or maintenance before withdrawing them which is a great shame. The worst examples are only fit for scrap I believe.

 

[Juniper Driver]

Of course they are sister units to 314,315,317's and 455's.

 

[61653 HTAFC]

Of course they are sister units to 314,315,317's and 455's.

317s are Mk3-based, not PEP. 455s are also Mk3-based, though as mentioned previously in this thread the 455/7s have one 508 TS. In fact, that's one reason the 'non-standard' argument about 508s on Lymington doesn't wash!

 

[tom1649]

313s are PEPs too of course.

 

[Juniper Driver]

317s are Mk3-based, not PEP. 455s are also Mk3-based, though as mentioned previously in this thread the 455/7s have one 508 TS. In fact, that's one reason the 'non-standard' argument about 508s on Lymington doesn't wash!

Fair enough I stand corrected,didn't really know a lot about the 317's anyway although I have travelled on them every now and again.Sorry.

Forgot about the 313's,knew I had forgot something.

 

[prod_pep]

Thats not what a Merseyrail DM once told me!

I'm afraid they were wrong then - they are both identical compressors as I say and have been fitted since new. The 508s have two compressors because they were once four car (it's the same design as the 315s).

 

[Helvellyn]

317s are Mk3-based, not PEP. 455s are also Mk3-based, though as mentioned previously in this thread the 455/7s have one 508 TS. In fact, that's one reason the 'non-standard' argument about 508s on Lymington doesn't wash!

It's a trailer car in the Class 455/7s, with very few electrical parts. Introducing Class 508s to SWT means introducing a totally different type of traction, that SWT Drivers and Guards would have to be trained up on and that SWT would have to find somewhere to base and then train maintenance staff to look after them, plus start acquiring a new set of spare parts for that (small) fleet. So a whole lot of expense for what? Just so you can have a 508 on the Lymington branch?

 

[tom1649]

It's a trailer car in the Class 455/7s, with very few electrical parts. Introducing Class 508s to SWT means introducing a totally different type of traction, that SWT Drivers and Guards would have to be trained up on and that SWT would have to find somewhere to base and then train maintenance staff to look after them, plus start acquiring a new set of spare parts for that (small) fleet. So a whole lot of expense for what? Just so you can have a 508 on the Lymington branch?

I'm sure you've summed up the TOC's feelings perfectly.
However, unless I'm missing something this didn't stop Chiltern introducing Class 121 bubble cars did it? That must have been shown to be cost effective.

My main gripe is electric rolling stock sitting idle while DMUs could be used where an increase in capacity is desperately needed. Ok some of the 508s are knackered but they shouldn't have been allowed to fall into that state in the first place.

 

[Helvellyn]

However, unless I'm missing something this didn't stop Chiltern introducing Class 121 bubble cars did it? That must have been shown to be cost effective.

My main gripe is electric rolling stock sitting idle while DMUs could be used where an increase in capacity is desperately needed. Ok some of the 508s are knackered but they shouldn't have been allowed to fall into that state in the first place.

Chiltern already had a couple of 121s for sandite/route learning duties, so adding an additional unit probably involved minimal cost. It also allowed them to release a Class 165 for use elsewhere on their own network. Many who suggest SWT use a 508 on the Lymington branch then expect the released 158 to be sent to another TOC, so it incurs the cost of introducing a non-standard unit but gets none of the benefit of using the released 158! The same applied to Arriva Trains Wales - the 121 'bubble' on the Cardiff Bay branch let them utilise another unit elsewhere themselves, so any extra cost to operating it was offset by the benefit to the TOC.

I agree the 508s shouldn't have been allowed to get in the state they did. However, with regard to SWT using 158s on the Lymington branch it makes sense for them as they have a small fleet of them that can be productively used (for them) on Hampshire local services, as well as to strengthen some services to London from Salisbury.

In an ideal world the Salisbury-Romsey-Eastleigh/Redbridge routes would be electrified and SWT would have a small fleet of 3-car 450s for use on the Salisbury 'figure of 6', Portsmouth-Southampton, Brockenhurst-Lymington and Basingstoke-Eastleigh-Southampton/Portsmouth local services.

 

[BlythPower]

Am I right in assuming the story in this month's Rail Express that London Overground are looking into taking up some of the spare 508s is an April Fool? :cry: Would've been nice if it were true - apart from the bit about merging them into 4-car units... :mad: