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Confused over TOPS multiple unit numbers.

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Saperstein

Saperstein

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Hi,

I always under stood that multiple unit numbers under TOPS were defined thus:

1xx DMU
2xx DEMU
3xx AC or dual voltage EMU
4xx DC EMU
9xx Departmental

Is the above correct? Also why are some DC units numbered 5xx?

And 7xx is another odd one? Some bran new units are being given 7xx such as Merseyrail’s 777 and yet others such as Northern ‘s 331 aren't.

Thanks.
 
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RailUK Forums

61653 HTAFC

61653 HTAFC

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The 5xx numbers are/were supposedly for DC units outside of the Southern region, hence 501s (Watford DC) 502 & 503 (Merseyrail), 504 (Bury) and 506 (Glossop/Hadfield).

Though I did hear that 455s were almost classified as 510s when new.

Then there's the Tyneside DC units, but they had moved South by the time TOPS came in.

The 7xx and 8xx are recent new additions to the ranges.
 
S

swt_passenger

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It’s all in a rail group standard here:
https://catalogues.rssb.co.uk/rgs/standards/RIS-2453-RST Iss 1.pdf
Please see Table 7 on page 32
400-599 is combined as DC EMUs now.
The 7xx range has been split since it was newly introduced:
700-749 AC or dual voltage EMUs
750-790 Bi-mode multiple units
(So it’s arguable the 777s are now misnumbered)
There’s also 600-699 available for DMUs, but I don’t think any have been used yet?
800 is high speed fixed formation trains, whatever the power mode.

It’s also important to note that the “new” ranges are not replacements, numbers in the existing traditional ranges are still available if currently unused.
 
hexagon789

hexagon789

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Saperstein said:
Hi,

I always under stood that multiple unit numbers under TOPS were defined thus:

1xx DMU
2xx DEMU
3xx AC or dual voltage EMU
4xx DC EMU
9xx Departmental

Is the above correct? Also why are some DC units numbered 5xx?

And 7xx is another odd one? Some bran new units are being given 7xx such as Merseyrail’s 777 and yet others such as Northern ‘s 331 aren't.

Thanks.
Click to expand...

I think the best approach is not to expect it to make perfect sense or for everything to nearly fit into groupings of numbers! ;)

Some make sense and are very logical, other classes don't always fit neatly but more roughly.
 
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gg1

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I know that ultimately it doesn't really matter and many people don't care one way or the other but it does irritate me when unused class numbers are skipped in favour of something snappier.

Don't even get me started on the 7xx and 8xx series when there are large numbers of unused 3xx class numbers available.
 
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norbitonflyer

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gg1 said:
Don't even get me started on the 7xx and 8xx series when there are large numbers of unused 3xx class numbers available.
Click to expand...
Quite - the rot set in with the 365s - the number chosen possibly because they were related to the 165s and 465s (although 165 was itself a jump from the previous number, 159)
There are still, including withdrawn classes, less than 70 classes used in the number ranges 3xx, 7xx and 8xx

Had they just continued from 325 (with the 365s as class 324), and assuming that, as in real life
- only SWT, Gatwick Express and Island Line numbered new stock in the 4xx series),
- high speed stock would be numbered in the 37x range (following the APT)
- tram trains would have their own series (say 39x)
- so would non-high speed electro diesels (say 36x)

Class 350 for ordinary ac or ac/dc emus (the latest being class 730)

Classes 360-363 for bi- and tri-mode (Classes 755, 756, 768, 769)

Class 371-381 for high speed (including Eurostar and IEPs - classes 39x and 8xx)
 
G

Glaswegian

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swt_passenger said:
It’s all in a rail group standard here:
https://catalogues.rssb.co.uk/rgs/standards/RIS-2453-RST Iss 1.pdf
Please see Table 7 on page 32
400-599 is combined as DC EMUs now.
The 7xx range has been split since it was newly introduced:
700-749 AC or dual voltage EMUs
750-790 Bi-mode multiple units
(So it’s arguable the 777s are now misnumbered)
There’s also 600-699 available for DMUs, but I don’t think any have been used yet?
800 is high speed fixed formation trains, whatever the power mode.

It’s also important to note that the “new” ranges are not replacements, numbers in the existing traditional ranges are still available if currently unused.
Click to expand...
There is an experimental hydrogen powered unit with a 614 number.
 
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Ribbleman

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swt_passenger said:
Yes, but even then, does that necessarily make them real bimodes?
Click to expand...
Of course, they were ordered before battery technology had developed sufficiently that it has been possible to alter the specification to install large batteries, so that services can be extended beyond the limits of the 3rd rail. Merseytravel were given a choice of class numbers by the Rolling Stock Library. I don’t know what the options were but they picked 777. Initially, seven sets of the current order will have the large batteries fitted.
 
S

swt_passenger

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Ribbleman said:
Of course, they were ordered before battery technology had developed sufficiently that it has been possible to alter the specification to install large batteries, so that services can be extended beyond the limits of the 3rd rail. Merseytravel were given a choice of class numbers by the Rolling Stock Library. I don’t know what the options were but they picked 777. Initially, seven sets of the current order will have the large batteries fitted.
Click to expand...
You’ve 2 years more information than when this was first discussed…
 
N

norbitonflyer

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59CosG95 said:
I seem to remember that various freight wagons introduced after privatisation took up lots of the 3xx numbers...
Click to expand...
They did, but that doesn't seem to matter any more. Some of the new 6-digit emu car numbers duplicate unit numbers. For example

Class 701 cars in the 4840xx range
Class 717 cars in the 4560xx range
Class 720 cars in the 4505xx range
Class 745 cars in the 3130xx and 3320xx ranges

(Classes 456 and 332 have since been withdrawn, but the duplication did exist)
 
XAM2175

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norbitonflyer said:
They did, but that doesn't seem to matter any more. Some of the new 6-digit emu car numbers duplicate unit numbers.
Click to expand...
Duplication between unit numbers and vehicle numbers is perfectly acceptable. It's locomotive class numbers that have to be checked against vehicle numbers, because locos are also vehicles.
 
WarrenTManager

WarrenTManager

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swt_passenger said:
It’s all in a rail group standard here:
https://catalogues.rssb.co.uk/rgs/standards/RIS-2453-RST Iss 1.pdf
Please see Table 7 on page 32
400-599 is combined as DC EMUs now.
The 7xx range has been split since it was newly introduced:
700-749 AC or dual voltage EMUs
750-790 Bi-mode multiple units
(So it’s arguable the 777s are now misnumbered)
There’s also 600-699 available for DMUs, but I don’t think any have been used yet?
800 is high speed fixed formation trains, whatever the power mode.

It’s also important to note that the “new” ranges are not replacements, numbers in the existing traditional ranges are still available if currently unused.
Click to expand...
One 777 at least is battery capable, giving two modes.
 
Wivenswold

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Dare I say it but I think it's probably time for a new numbering system. It's all gotten a bit messy, TOPS must be 50 years old now, the coming of GBR may be a good time for a change.
 
D365

D365

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Wivenswold said:
Dare I say it but I think it's probably time for a new numbering system. It's all gotten a bit messy, TOPS must be 50 years old now, the coming of GBR may be a good time for a change.
Click to expand...
Other than for spotter ”neatness”, in what way does the current system not do its job?
 
hexagon789

hexagon789

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Wivenswold said:
Dare I say it but I think it's probably time for a new numbering system. It's all gotten a bit messy, TOPS must be 50 years old now, the coming of GBR may be a good time for a change.
Click to expand...
Does it matter if it's "messy" though? Each "class" has an identifier, if they don't all fit neatly into a pattern it doesn't affect the ability to differentiate. The TOPS computer system itself is indeed outdated but if it still functions as required is it worth all the expenditure of replacing it?
 
YorksLad12

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Wivenswold said:
Dare I say it but I think it's probably time for a new numbering system. It's all gotten a bit messy, TOPS must be 50 years old now, the coming of GBR may be a good time for a change.
Click to expand...
That's a bit like saying Dewey Decimal Classification is a bit messy and needs replacing.

Which it is, but it gets tinkered with regularly rather than junked. The equivalent tinkering with TOPS introduced the 7xx and 8xx classes, which will slowly kill off the 1xx and 2xx classes.
 
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