Multiple Working, progression or regresion

[Roast Veg]

Now as an alternative if even one manufacturer open-sourced their transmission protocol, that would change everything. It's a shame that there's no financial incentive in doing so (indeed, the opposite is true), but the written public definition of some modern standard would open many doors for digital compatibility.

 

[SpacePhoenix]

Is the functionality of what each pin of the electrical connector us used for standardised at all?

 

[Crossover]

Is the functionality of what each pin of the electrical connector us used for standardised at all?

I don't believe so, no

 

[61653 HTAFC]

Is the functionality of what each pin of the electrical connector us used for standardised at all?

I don't believe so, no

Example: the autocoupler set-up on sprinters versus Turbos (165/166). Allegedly the Turbos were deliberately specified (by NSE) to be incompatible with Sprinters to prevent 16x being "nicked" by Provincial!

 

[swt_passenger]

Is the functionality of what each pin of the electrical connector us used for standardised at all?

No, definitely not. Have a browse through the 156 pages of RSSB information here: https://www.rssb.co.uk/rgs/reldocs/sd001 iss 2.pdf They list at least 38 functionally different designs of electrical connector.

 

[Kneedown]

DMU's had several coupling codes but the main was blue star so DMU's from Inverness to Plymouth were on the whole able to work in multiple

Not being pedantic, but just for info first gen DMU's mostly had a blue SQUARE coupling code.
Blue star was for loco's although some loco's such as 50's, 56's, 58's for example had different codes. Orange square and red diamond respectively.

 

[jopsuk]

There's a comprehensive list of BR multiple working codes here

 

[coppercapped]

Fascinating info, copper, as always! One thing you don't mention though is the dreaded TMS. Regardless of physical coupler compatibility, is it not realistically the case that manfacturers appear to scupper any hope of common sense by using different software every time they build something?! A driver friend tells me that even different subclasses of Electrostar in the same fleet can't play together because their computers aren't friends. That seems utterly ludicrous, the Electrostar factory has surely been churning out essentially the same train for the past 15 years. And yet a Turbostar will talk to a Sprinter! Presumably the various manufacturers' TMS software creation is outsourced to a (the same?) third party provider? Or do the factories maintain their own software departments?

Hmmm...! The TMS! This is an area I haven't really looked at but looking at the issues from that part of my past professional life involved in computer manufacture I would think that each train manufacturer would at least specify what they need. This is because they know what their hardware should do and they have their own ideas of what the driver and maintenance staff need to know.

Whether they write the code themselves, or sub-contract some or all of it to third parties, is their decision. On top of this the TMS will almost certainly be an application written to run on a general purpose computer using a readily available operation system. This latter is most likely be one on the Windows variants, Linux or one of the Unixes - it will be difficult to find enough people to write code running on one of the more abstruse OSes such as Mach or BeOS and to maintain it twenty years down the line.

The other factor is that the TMS is a comparatively new idea for trains. As a result they are evolving quite quickly at the moment so trying to define a standard TMS for use by different manufacturers would be very difficult. What might be possible in a few years time is that the driver's user interface is consistent between manufacturers, even if there are some differences depending on the individual train designs and capabilities.

 

[Taunton]

Despite the different coupling codes on classic dmus, they were all really variations on a theme. The initial Yellow Diamond moved on to the standard Blue Square mainly with improved engine starting circuitry, which could have been usefully standardised but was deemed not worthwhile. The main difference was between cars with manual gearchange (most of them) and those with automatics. It will be apparent that a drivers desk of an automatic would have no means to control a manual gearbox. In fact the earlier automatic units did even provide for this, with an extra button to change gears up/down on any trailing manual unit, but the risk of the driver forgetting about this and pulling a manual gearchange unit too fast in low gear was unfortunately borne out in practice, there was a fire, and the different codes were introduced.

The AAR MU system is somewhat dismissed above but US railroads, with locomotives from a range of manufacturers, have not had anything else for the last 70 years. It has integrated perfectly with computer control, slow speed control, and all modern innovations. You can multiple a vintage switcher with a current all-electronic main line locomotive, plus anything else from any manufacturer, and drive the whole lot from any cab. Don't say it's not clever; it is.

The Kentish Town calamitous breakdown of a few years ago on Thameslink shows the real hazards of incompatible trains. If there was a breakdown, the plan was it would be pushed to the next station by the following train. Seemingly in isolation of this, the operator had stocked up on two types of train with incompatible couplings. And then, in isolation again, the timetable planners had devised a timetable where alternate trains were formed of the two different types of stock, so it was impossible for the rescue plan to work.