Compatibility between different unit classes and rolling stock types in other countries.

[stadler]

When i was last in Croatia around 2018 or 2019 i went on two trains that were formed of a 6111 unit and 6112 unit coupled together. These were in passenger service and operated without issue. It amazed me that two EMU types that had 40 years age difference and were built by two different unrelated manufacturers were fully compatible.

The 6111s are old Yugoslav EMUs built in the mid 1970s by Ganz. The 6112s are new Croatian EMUs built in the mid 2010s by Koncar. These units have approximately 40 years age difference between them but yet are fully compatible. They can be driven from either unit and all the electronics and door control and everything works fine in both units.

In the UK even most modern stuff built in the same era by the manufacturer and the same rolling stock family can not be coupled (for example 375s and 377s are incompatible and 377s and 387s are incompatible) except for emergencies or empty stock workings. So it really surprises me how compatible some Mainland European trains are. They make everything far more compatible.

I would be interested to know the situation in other countries in Mainland Europe or even elsewhere around the world? Do any other countries do compatibility between different types of DMUs and EMUs very well and are there any other examples that you can think of?

Also what is the biggest age difference between unit types that are compatible with each other? Are there any other units like the Croatian example with massive age differences that are still compatible?

I know locomotives and carriages are generally far more compatible so there are probably dozens of examples of these. But the DMUs and EMUs surprise me the most as these tend to have less compatibility.

I remember also seeing some very weird combinations in Poland and Czech Republic of DMUs and EMUs hauling locomotive hauled carriages. I have also seen two DMUs or EMUs with locomotive hauled carriages sandwiched between them.

I am mainly interested in examples of different types coupled in passenger service. So not really empty stock moves or emergency rescues.

 

[DanielB]

An oddity in the Netherlands are the Stadler GTW units operated by Arriva Limburg (which were originally purchased by Veolia): here the EMUs and DMUs are capable of running together on electrified routes. The DMUs are therefore also the only diesel-powered GTWs in the Netherlands having a button in the cab to raise (and lower) the pantograph of the EMU.

 

[JonasB]

The ones I can think of are the so called Y6-series used by SJ from the early 50s to the late 80s. SJ designed them and they were built by four different companies, ASJ, Hägglund & söner, Kalmar Verkstad and Märstaverken.

There are three DMUs, Y6, Y7 and Y8, two EMUs, X16 and X17 and a number of different trailers. And they could all be coupled together. https://en.wikipedia.org/wiki/SJ_Y6

 

[Bemined]

In the past it was pretty common for Dutch stock to be compatible, the '35, '36, '40, '46, '54 and '57 stock could be coupled together. Last year they actually did that again with two museum units: https://nieuws.ns.nl/onderweg-met-muizeneus-en-hondekop-tijdens-open-monumentendag/ (in dutch).

Not just trains had this feature, on the metro in Rotterdam the SG2 stock could be coupled with the older MG2 stock and even with the engineering stock. They last used that feature when they opened the extension to Nesselande by coupling a decorated flatbed car in front of the trainset with the guests.

 

[bahnause]

As a general rule, vehicles are made compatible where it makes operational sense. This process involves more than just approval; it also includes all subsequent modifications and software updates. Even identical vehicles from different TOCs require significant work, as the requirements of one TOC cannot necessarily be transferred to the vehicle software of another.

Another issue is adapting components to standards in different batches of 'identical' vehicles. The SBB's RABe512 is one example: it was ordered as an additional option from the RABe511 order. However, three-quarters of all components are not identical, and the bus system is also based on a new generation. Only the vehicles necessary for operation of the 'old' RABe511 were made compatible through software and hardware updates.

 

[DanielB]

Another one from the Netherlands: DH1/DH2 and DM'90 were also capable of being coupled in passenger service. Found this photo on wikipedia.

In the past it was pretty common for Dutch stock to be compatible, the '35, '36, '40, '46, '54 and '57 stock could be coupled together. Last year they actually did that again with two museum units: https://nieuws.ns.nl/onderweg-met-muizeneus-en-hondekop-tijdens-open-monumentendag/ (in dutch).

To add to that, here is a photo of that combination...

NSM 273 + NSM 386 - Utrecht, Biltstraat by Daniël Bleumink, on Flickr

There is also an example from Germany, where the RE1 Koblenz - Mannheim (a DB FLIRT) is combined with a CFL KISS till Trier, from where the KISS continues to Luxembourg)

 

[MarcVD]

All EMUs built for SNCB between 1939 and 1981 - 540 of them - were all compatible together and regularly mixed together without any regard whatsoever to the differences between them. Just mix 'em and run.

 

[jpl]

In Finland VR's Sr2 and Sr3 electric locos are now compatible together but rarely mixed together. I've only recently seen Sr3 + Sr2 combination in a sleeper. Sr2's were retrofitted with a module which simulates a driver handling controls. The module was originally built for compatibility with Edo driving van trailers.