Is TOPS numbering all over the shop?

[Sunil_P]

When I first got interested in trains as a kid during the 1980s, the TOPS numbering system seemed to be rather simple, and made a lot of sense.

So you had :

diesel locos: 01-69
DC electric locos 70-79
AC electric locos 80-89
Departmental: 97
Steam: 98 (Vale of Rheidol, when it was BR!)
BR ferries: 99 (not trains, obvs.)
DMUs: 100-199
DEMUs: 200-210
EMUs AC: 300-399
EMUs DC: 400-499 (ex-SR network)
EMUs DC: 500-508 (non-SR)
Departmental: 900s

But nowadays you have AC EMUs numbered in the 7xxs and 8xxs (what happened to the unused 3xx ??), and some diesels in the 70s (why no Class 61/62/63/64/65 etc.?).

For example, around east London, you have Bombardier Aventras numbered 345 and 710.

Anyway, I'm sure there's an explanation!

 

[JonathanH]

why no Class 61/62/63/64/65 etc.?

Those series were used for carriage numbers in the electric multiple unit fleet.

 

[swt_passenger]

Loads of previous threads about this. It’s almost 10 years since the new number ranges were publicised:
This is a list of threads with TOPS in the title, there are quite a few others.

Search results for query: Tops

 

[ainsworth74]

Anyway, I'm sure there's an explanation!

Whereas I'm sure you're going to be disappointed if you're expecting one that makes sense or is logical

 

[XAM2175]

But nowadays you have AC EMUs numbered in the 7xxs and 8xxs (what happened to the unused 3xx ??), and some diesels in the 70s (why no Class 61/62/63/64/65 etc.?).

These are the current arrangements per the relevant standard:

British Rail locomotive and multiple unit numbering and classification - Wikipedia

en.wikipedia.org

 

[APT618S]

An inconsistency I see is the car numbering within a unit between different classes.
Compare the car numbering of 345 vs 720 where in one the 3rd digit changes between cars (720) and in the other the 4th digit changes between cars (345). I would have thought this would have been specified in the numbering procedure.

 

[norbitonflyer]

The multiple unit class numbering was quite logical until someone chose 165 for the Networker Turbos and 365 for the "Networker Express" to match the 465 Networkers (which did fit the SR scheme, 4x5 having always been 4-car suburban units (4SUB, 4EPB, 4PEP, 455, 4VEC).

Following previous convention they would probably have been classes 160 and 324 respectively, those being the next available numbers (157 was allocated to a class that was never built - the "Strathclyde Sprinter", and class 325 came later), although when running on the Southern and not fitted with a pantograph the 365s could logically have been 463.

But TOPS was always illogical in determining what was a class and what was a subclass.

Different gearing, and thus maximum speed, is the only thing differentaiating class 08 and 09, but some members of class 31 also had different gearing (although I suspect this was done in order to keep the number of Class 08s below 1,000)

Different ratings of engine justified two different classes of "Peak" (44/45), and both the BR and BRCW Type 2s were also split into two classes (24/25 and 26/27) on the basis of engine rating. But "Peaks" with a different make of electrical equipment were classified sepaerately (46) whilst Class 25s with e different electrical equipment were not.

The "Claytons" were all class 17, despite having two different makes (not just rating) of engine and two different makes of electrical equipment, and two coupling codes.

Class 73s kept their class number despite a rebuilding even more extensive than those applied to classes 47 and 56, which became classes 57 and 69 respectively.

Some DMUs and EMUs differ in quite trivial ways (158/159, 321/322) whilst much more significant differences were absorbed into single classes (e.g the various flavours of classes 159, 305 and 308). There is also the whole mess of electrostar classification, with considerable variation between subclasses of classes 375 and 377, and no obvious reason why classes 357, 379 and 387 could not be further subclasses of 375 and/or 377.

 

[Irascible]

Class 73s kept their class number despite a rebuilding even more extensive than those applied to classes 47 and 56, which became classes 57 and 69 respectively.

That, I am curious about, coz I always thought they ( rather than the 71->74 ) were more or less as built ( unless you just mean the very recent rebuild? )

 

[pdeaves]

That, I am curious about, coz I always thought they ( rather than the 71->74 ) were more or less as built ( unless you just mean the very recent rebuild? )

I think norbitonflyer meant the recent rebuilds (47 -> 57, 56 -> 69 but 73 -> 73)