On Oct 31, 7:22*pm, The Gardener wrote:

Looking at my 1984 copy of "Southern Region Multiple Unit Trains",
published by the SEG, all EMUs were allocated a Traction Motor Index,
usually equivalent to the number of traction motors in a unit, and the
maximum TMI allowed was 16. So a 16-car formation of any units apart
from 4REPs would have been permissible. TMIs that did not correspond
to the number of vehicles or for locos etc were (as quoted in the
book):
4REP 14
Class 73 8
GLV 2
MLV 2 (this is not quoted but is my belief).

While that is more or less correct data it is not the whole picture.

MLV = 2 is correct (68000 would have been 4 had it run for SR, which
it did not).

One small error too, its called Conductor Rail Index not Traction
Motor Index, although for "standard" units it is a count of 1 for
every EE507 motor in the train, which happens to work out as
equivalent 1 for every car.

EE546 motors were the non standard ones - but you've picked those up
anyway, under 73s and 4Reps. AFAIR, 74s were 12 but I'd need to check
on that. On DC traction, the GEC motors in 319s count the same as
EE507s; a 508/313s although 8 motors per 4/3car units are still index
4 because the motors are approx half size/power each.

16 was the maximum index permitted, except where lower limits apply
(e.g. Lymington, Seaford), but that only looks at electrical load -
there were other coupling restrictions in place which - apart from
locations shorter than 12cars - limited all EMU trains to 12cars**
except where specifically authorised - the most notable exception,
indeed the only exception I can think of, was channel ports boat
trains that were allowed to be 14car either 12Cep+2MLV or 12Cep+TLV
+MLV.

Exceeding index 12 was also only where specifically authorised. Again
applies to boat trains, which were 14 or 16 depending if the 12Cep was
with MLV+TLV or 2MLV. The only other exception to not exceeding 12 was
anything to do with 4Reps and EDLs - 4Rep+de-icer (14+2) was allowed
anywhere where Reps normally worked, 2x73 = 16 but there are again
limits where this can be done. Weymouth used to not allow 2x73 on
electric but it can now (ignoring the recent temporary reimposition of
that limit because of grid feeder problems in Dorset).

The were 2 reported occasions I can think of when it happened that 4 x
3Cep got mated together, this was not supposed to happen but
inevitably did when assorted 4Cep and 3Cep attaching and detcahing
portions started out OK but later in the day got out of phase at
Ramsgate or Faversham or Ashford.

There was a SEG railtour that was a solo 4Rep but because of an m.g.
failure ended up in m.u. with a 4Cep which was index 18 - and we did
trip at least one sub-station breaker in Kent.

It was not unknown for longer trains to run ECS at night - I have
heard tales or 16 or 20 or 24EPB being moved between berthing points
resolving previous days disruption ready for next days service. But
all such moves are done without any other trains around.


Returning to coupling limits, when you look at 12EPB it was not
possible to couple together any old permutation of EPB stock. BR
Standard Mk1 4EPB had buckeye couplers and push-pull plates between
the intermediate cars unlike SR 4EPB which had short three link chains
and single buffers. AFAIR 12EPB was not permitted if all units were BR
EPB: I'm sure it happened, so theres no need for anyone to cite every
time it did, I'm just saying it was not supposed to.

There are similar coupling limits on modern stock today e.g on central
lines you car run 8car 455/456 of 455+455 or 455+456+456 but
456+456+456+456 is not allowed, they are too long for a couple of
vital platforms. Likewise on the eastern side where 10car trains
operate, 465+465+466 is allowed, but (I think) 465+466+466+466 and
466+466+466+466+466 is not.


** before anyone piles in and point out 373s were longer, the
Conductor Rail Index system did not apply to those. CRI apply only to
DC motor trains - so up to and including 456 and 319 have indices,
from 465/466 onwards do not.


--
Nick

On Oct 31, 7:22*pm, The Gardener wrote:
On Oct 31, 6:04*pm, Nick wrote:





On Oct 31, 12:16*pm, "Peter Masson" wrote:

"Nick Leverton" wrote

I don't remember there being any restriction on that in control terms.
Up to about 1969/70, MLV+MLV+Cep+Bep+Cep was common on boat trains -
effectively five units. *I think I recall workings later on such as
8Hap - four units. *My early notebooks unfortunately didn't include
train formations.

I've got a note that I travelled on a 5 unit train, 0910 Charing Cross to
Folkestone, in 1971 orv 1972, 5x2HAP from Charing Cross, rear 4 detached at
Tonbridge. I also have a note of a 4-unit train in 1971, 0940 Victoria to
Ramsgate formed 2HAP, 2HAP, 4BEP, 4CEP, rear 4 detached at Faversham for
Dover.

Peter

ISTR a 6x2HAP in the 1983/84 timetable which was an evening rush hour
train from Waterloo to Basingstoke/Alton, splitting at Woking, half
going to each destination.

Nick

Looking at my 1984 copy of "Southern Region Multiple Unit Trains",
published by the SEG, all EMUs were allocated a Traction Motor Index,
usually equivalent to the number of traction motors in a unit, and the
maximum TMI allowed was 16. So a 16-car formation of any units apart
from 4REPs would have been permissible. TMIs that did not correspond
to the number of vehicles or for locos etc were (as quoted in the
book):

4REP 14
Class 73 8
GLV 2
MLV 2 (this is not quoted but is my belief).


While that is more or less correct data it is not the whole picture.

MLV = 2 is correct (68000 would have been 4 had it run for SR, which
it did not).

One small error too, its called Conductor Rail Index not Traction
Motor Index, although for "standard" units it is a count of 1 for
every EE507 motor in the train, which happens to work out as
equivalent 1 for every car.

EE546 motors were the non standard ones - but you've picked those up
anyway, under 73s and 4Reps. AFAIR, 74s were 12 but I'd need to check
on that. On DC traction, the GEC motors in 319s count the same as
EE507s; a 508/313s although 8 motors per 4/3car units are still index
4 because the motors are approx half size/power each.

16 was the maximum index permitted, except where lower limits apply
(e.g. Lymington, Seaford), but that only looks at electrical load -
there were other coupling restrictions in place which - apart from
locations shorter than 12cars - limited all EMU trains to 12cars**
except where specifically authorised - the most notable exception,
indeed the only exception I can think of, was channel ports boat
trains that were allowed to be 14car either 12Cep+2MLV or 12Cep+TLV
+MLV.

Exceeding index 12 was also only where specifically authorised. Again
applies to boat trains, which were 14 or 16 depending if the 12Cep was
with MLV+TLV or 2MLV. The only other exception to not exceeding 12 was
anything to do with 4Reps and EDLs - 4Rep+de-icer (14+2) was allowed
anywhere where Reps normally worked, 2x73 = 16 but there are again
limits where this can be done. Weymouth used to not allow 2x73 on
electric but it can now (ignoring the recent temporary reimposition of
that limit because of grid feeder problems in Dorset).

The were 2 reported occasions I can think of when it happened that 4 x
3Cep got mated together, this was not supposed to happen but
inevitably did when assorted 4Cep and 3Cep attaching and detcahing
portions started out OK but later in the day got out of phase at
Ramsgate or Faversham or Ashford.

There was a SEG railtour that was a solo 4Rep but because of an m.g.
failure ended up in m.u. with a 4Cep which was index 18 - and we did
trip at least one sub-station breaker in Kent.

It was not unknown for longer trains to run ECS at night - I have
heard tales or 16 or 20 or 24EPB being moved between berthing points
resolving previous days disruption ready for next days service. But
all such moves are done without any other trains around.


Returning to coupling limits, when you look at 12EPB it was not
possible to couple together any old permutation of EPB stock. BR
Standard Mk1 4EPB had buckeye couplers and push-pull plates between
the intermediate cars unlike SR 4EPB which had short three link chains
and single buffers. AFAIR 12EPB was not permitted if all units were BR
EPB: I'm sure it happened, so theres no need for anyone to cite every
time it did, I'm just saying it was not supposed to.

There are similar coupling limits on modern stock today e.g on central
lines you car run 8car 455/456 of 455+455 or 455+456+456 but
456+456+456+456 is not allowed, they are too long for a couple of
vital platforms. Likewise on the eastern side where 10car trains
operate, 465+465+466 is allowed, but (I think) 465+466+466+466 and
466+466+466+466+466 is not.


** before anyone piles in and point out 373s were longer, the
Conductor Rail Index system did not apply to those. CRI apply only to
DC motor trains - so up to and including 456 and 319 have indices,
from 465/466 onwards do not.


--
Nick

On Oct 31, 8:47*pm, D7666 wrote:

. AFAIR 12EPB was not permitted if all units were BR
EPB:



Correction

Thats supposed to say AFAIR **10**EPB was not permitted on SED
suburban diagrams if all units were BR EPB.

--
Nick

In article ,
(John C) wrote:

"Peter Masson" wrote in message
...

"Nick Leverton" wrote

I don't remember there being any restriction on that in control terms.
Up to about 1969/70, MLV+MLV+Cep+Bep+Cep was common on boat trains
-
effectively five units. I think I recall workings later on such as
8Hap - four units. My early notebooks unfortunately didn't include
train formations.

I've got a note that I travelled on a 5 unit train, 0910 Charing
Cross to Folkestone, in 1971 orv 1972, 5x2HAP from Charing Cross,
rear 4 detached at Tonbridge. I also have a note of a 4-unit train
in 1971, 0940 Victoria to Ramsgate formed 2HAP, 2HAP, 4BEP, 4CEP,
rear 4 detached at Faversham for Dover.

10 car EPB formations formed entirely of two car sets were not
unusual in the last few months, especially once the Selhurst units
moved to Slade Green sending many of the unrefurbished four car sets
for scrap.

But these were from another era of much simpler multiple unit control
systems. What about modern units with computers?

--
Colin Rosenstiel

wrote in message
...
In article ,
(John C) wrote:

"Peter Masson" wrote in message
...

"Nick Leverton" wrote

I don't remember there being any restriction on that in control terms.
Up to about 1969/70, MLV+MLV+Cep+Bep+Cep was common on boat trains
-
effectively five units. I think I recall workings later on such as
8Hap - four units. My early notebooks unfortunately didn't include
train formations.

I've got a note that I travelled on a 5 unit train, 0910 Charing
Cross to Folkestone, in 1971 orv 1972, 5x2HAP from Charing Cross,
rear 4 detached at Tonbridge. I also have a note of a 4-unit train
in 1971, 0940 Victoria to Ramsgate formed 2HAP, 2HAP, 4BEP, 4CEP,
rear 4 detached at Faversham for Dover.

10 car EPB formations formed entirely of two car sets were not
unusual in the last few months, especially once the Selhurst units
moved to Slade Green sending many of the unrefurbished four car sets
for scrap.

But these were from another era of much simpler multiple unit control
systems. What about modern units with computers?

--
Colin Rosenstiel

There was something about Group E and Group D stock and I can't find it in
my files.

wrote in message
...
In article ,
(John C) wrote:

"Peter Masson" wrote in message
...

"Nick Leverton" wrote

I don't remember there being any restriction on that in control terms.
Up to about 1969/70, MLV+MLV+Cep+Bep+Cep was common on boat trains
-
effectively five units. I think I recall workings later on such as
8Hap - four units. My early notebooks unfortunately didn't include
train formations.

I've got a note that I travelled on a 5 unit train, 0910 Charing
Cross to Folkestone, in 1971 orv 1972, 5x2HAP from Charing Cross,
rear 4 detached at Tonbridge. I also have a note of a 4-unit train
in 1971, 0940 Victoria to Ramsgate formed 2HAP, 2HAP, 4BEP, 4CEP,
rear 4 detached at Faversham for Dover.

10 car EPB formations formed entirely of two car sets were not
unusual in the last few months, especially once the Selhurst units
moved to Slade Green sending many of the unrefurbished four car sets
for scrap.

But these were from another era of much simpler multiple unit control
systems. What about modern units with computers?

--
Colin Rosenstiel

Can't cope with a snowflake!

On Oct 31, 8:47*pm, D7666 wrote:
On Oct 31, 7:22*pm, The Gardener wrote:

Looking at my 1984 copy of "Southern Region Multiple Unit Trains",
published by the SEG, all EMUs were allocated a Traction Motor Index,
usually equivalent to the number of traction motors in a unit, and the
maximum TMI allowed was 16. So a 16-car formation of any units apart
from 4REPs would have been permissible. TMIs that did not correspond
to the number of vehicles or for locos etc were (as quoted in the
book):
4REP 14
Class 73 8
GLV 2
MLV 2 (this is not quoted but is my belief).

While that is more or less correct data it is not the whole picture.

MLV = 2 is correct (68000 would have been 4 had it run for SR, which
it did not).

One small error too, its called Conductor Rail Index not Traction
Motor Index, although for "standard" units it is a count of 1 for
every EE507 motor in the train, which happens to work out as
equivalent 1 for every car.

EE546 motors were the non standard ones - but you've picked those up
anyway, under 73s and 4Reps. AFAIR, 74s were 12 but I'd need to check
on that. On DC traction, the GEC motors in 319s count the same as
EE507s; a 508/313s although 8 motors per 4/3car units are still index
4 because the motors are approx half size/power each.

16 was the maximum index permitted, except where lower limits apply
(e.g. Lymington, Seaford), but that only looks at electrical load -
there were other coupling restrictions in place which - apart from
locations shorter than 12cars - limited all EMU trains to 12cars**
except where specifically authorised - the most notable exception,
indeed the only exception I can think of, was channel ports boat
trains that were allowed to be 14car either 12Cep+2MLV or 12Cep+TLV
+MLV.

Exceeding index 12 was also only where specifically authorised. Again
applies to boat trains, which were 14 or 16 depending if the 12Cep was
with MLV+TLV or 2MLV. The only other exception to not exceeding 12 was
anything to do with 4Reps and EDLs - 4Rep+de-icer (14+2) was allowed
anywhere where Reps normally worked, 2x73 = 16 but there are again
limits where this can be done. Weymouth used to not allow 2x73 on
electric but it can now (ignoring the recent temporary reimposition of
that limit because of grid feeder problems in Dorset).

The were 2 reported occasions I can think of when it happened that 4 x
3Cep got mated together, this was not supposed to happen but
inevitably did when assorted 4Cep and 3Cep attaching and detcahing
portions started out OK but later in the day got out of phase at
Ramsgate or Faversham or Ashford.

There was a SEG railtour that was a solo 4Rep but because of an m.g.
failure ended up in m.u. with a 4Cep which was index 18 - and we did
trip at least one sub-station breaker in Kent.

It was not unknown for longer trains to run ECS at night - I have
heard tales or 16 or 20 or 24EPB being moved between berthing points
resolving previous days disruption ready for next days service. But
all such moves are done without any other trains around.

Returning to coupling limits, when you look at 12EPB it was not
possible to couple together any old permutation of EPB stock. BR
Standard Mk1 4EPB had buckeye couplers and push-pull plates between
the intermediate cars unlike SR 4EPB which had short three link chains
and single buffers. AFAIR 12EPB was not permitted if all units were BR
EPB: I'm sure it happened, so theres no need for anyone to cite every
time it did, I'm just saying it was not supposed to.

There are similar coupling limits on modern stock today e.g on central
lines you car run 8car 455/456 of 455+455 or 455+456+456 but
456+456+456+456 is not allowed, they are too long for a couple of
vital platforms. Likewise on the eastern side where 10car trains
operate, 465+465+466 is allowed, but (I think) 465+466+466+466 and
466+466+466+466+466 is not.

** before anyone piles in and point out 373s were longer, the
Conductor Rail Index system did not apply to those. CRI apply only to
DC motor trains - so up to and including 456 and 319 have indices,
from 465/466 onwards do not.

--
Nick

Thanks for your clarification. You are, of course, right about the
term "conductor rail index number" - my fault for mis-reporting it.

On the subject of 12EPB, I can only once recall seeing such a
formation in service and that was on the first Network Day back in
1986, when at least one additional diagram ran between Victoria and
Brighton so formed. Unfortunately, I only have my memory to rely on
and don't have any photographic evidence to back this up.

On Oct 31, 9:15*pm, wrote:
But these were from another era of much simpler multiple unit control
systems. What about modern units with computers?


There it gets more complex.

375/377 configure themselves by current limiting. Its been posted in
here a few times before, but in simple terms each traction pack (or
motor bogie) takes 750 A but once a train reaches or exceeds 4500(?)
A, the train computers divide loads equally across all working packs
but not at 750 A. Or something like that. In this way the performance
of 4x3 (8 packs) is equalised with 3x4 (9 packs).

450/444 are not as smart, they (I think) are 2000 A each 444 and 1500
A each 450 - but as there are less possible permutations actually
don't need to be as complex as 375/377 - in practical terms none of
those you;d find working a train exceed 4500 A.

Overall there are many other scenarios, 465s, 458s, 460s, 376s, are
all different, but the concept is the same, it all works by current
limiting and is not necessarily dependent on number of cars or packs
or motors in the train.

--
Nick

On Oct 31, 9:31*pm, The Gardener wrote:

On the subject of 12EPB, I can only once recall seeing such a
formation in service and that was on the first Network Day back in
1986, when at least one additional diagram ran between Victoria and
Brighton so formed. Unfortunately, I only have my memory to rely on
and don't have any photographic evidence to back this up.

12EPB were used on Brighton bike ride reliefs - AFAIR the BR EPB
coupling thing did no apply here, as it was outside the SED side
suburban areas, BR 12EPB being no different to 12Vep in this respect.

--
Nick

In uk.railway D7666 wrote:
375/377 configure themselves by current limiting. Its been posted in
here a few times before, but in simple terms each traction pack (or
motor bogie) takes 750 A but once a train reaches or exceeds 4500(?)
A, the train computers divide loads equally across all working packs
but not at 750 A. Or something like that. In this way the performance
of 4x3 (8 packs) is equalised with 3x4 (9 packs).

There was that 23 car Southeastern 37x that ran as ECS during the snow last
winter. Obviously a special case with appropriate overrides, but I wonder
what was overridden. Highest current would be on starting I assume, and you
can't avoid that. Unless by a reduction in starting torque?

Theo