Multiple Unit Multiple Working Questions

[Masbroughlad]

Thinking out loud.....

My thought process started with why aren't EMR 222 units able to go to XC to work with 220/221? That snowballed....

Why can't 222s cascading from EMR go to XC (or GC) because incompatibility? Are they not of the same design? Could they not be modified?

Can 22X fleet work in multiple with other units such as 170, 175, 180, 185, 197s etc?

Can the 22X fleet work in multiple with 80X fleet? Can Pendolinos couple with Avanti 80X (whatever they have)?

I guess my question in a nutshell is which units can work in multiple with other units (after Sprinters)?

Do they have totally different couplers? Do they have multiple working codes like old loco and units had?

And if they fail, can any loco rescue them?

Anyone able to explain in layperson''s terms please?

TIA.

 

[InkyScrolls]

If you have a look on Wikipedia at the pages for MU classes the other classes they can work with are listed in the panel on right.

As for why (or not, as is usually the case!), many reasons!

 

[MCR247]

Thinking out loud.....

My thought process started with why aren't EMR 222 units able to go to XC to work with 220/221? That snowballed....

Why can't 222s cascading from EMR go to XC (or GC) because incompatibility? Are they not of the same design? Could they not be modified?

Can 22X fleet work in multiple with other units such as 170, 175, 180, 185, 197s etc?

Can the 22X fleet work in multiple with 80X fleet? Can Pendolinos couple with Avanti 80X (whatever they have)?

I guess my question in a nutshell is which units can work in multiple with other units (after Sprinters)?

Do they have totally different couplers? Do they have multiple working codes like old loco and units had?

And if they fail, can any loco rescue them?

Anyone able to explain in layperson''s terms please?

TIA.

Class 220s and 221s have different TMS software which means they wouldn’t be compatible to work in passenger service with Class 222s. They should be able to couple in emergency to rescue one another though

 

[Masbroughlad]

Is TMS train management system? Guessing at that!

If software or hardware could it not be changed in a deep refurbishment?

 

[Efini92]

Class 220s and 221s have different TMS software which means they wouldn’t be compatible to work in passenger service. They should be able to couple in emergency to rescue one another though

Do you mean 222’s and voyagers? 220’s and 221’s regularly work in multiple on XC.

Thinking out loud.....

My thought process started with why aren't EMR 222 units able to go to XC to work with 220/221? That snowballed....

Why can't 222s cascading from EMR go to XC (or GC) because incompatibility? Are they not of the same design? Could they not be modified?

Can 22X fleet work in multiple with other units such as 170, 175, 180, 185, 197s etc?

Can the 22X fleet work in multiple with 80X fleet? Can Pendolinos couple with Avanti 80X (whatever they have)?

I guess my question in a nutshell is which units can work in multiple with other units (after Sprinters)?

Do they have totally different couplers? Do they have multiple working codes like old loco and units had?

And if they fail, can any loco rescue them?

Anyone able to explain in layperson''s terms please?

TIA.

In short no, modern trains rely heavily on computers. If they don’t use the same software they are not compatible.

As for locos, providing there is an adapter coupler they can attach mechanically.

 

[MCR247]

Do you mean 222’s and voyagers? 220’s and 221’s regularly work in multiple on XC.

In short no, modern trains rely heavily on computers. If they don’t use the same software they are not compatible.

As for locos, providing there is an adapter coupler they can attach mechanically.

Corrected

 

[saismee]

As for locos, providing there is an adapter coupler they can attach mechanically.

Adding on, rescued trains are "dragged" and unpowered - the locomotive provides all the power and the unit is out of service. Multiple working allows all (or most) equipment on all units to function, such as lighting, pantographs, engines, motors, brakes. Software, electrics (such as voltage), and couplers are all individual issues between units. Take a look at most units fitted with scharfenberg couplers, the electrical contacts are often different.

An example is the 755 and 745. The 755s are fitted with electrical contacts to allow multiple working, but the 745's coupler has no contacts and the coupler is only used for rescuing, even though they are the same manufacturer and operator.

 

[Adrian1980uk]

Adding on, rescued trains are "dragged" and unpowered - the locomotive provides all the power and the unit is out of service. Multiple working allows all (or most) equipment on all units to function, such as lighting, pantographs, engines, motors, brakes. Software, electrics (such as voltage), and couplers are all individual issues between units. Take a look at most units fitted with scharfenberg couplers, the electrical contacts are often different.

An example is the 755 and 745. The 755s are fitted with electrical contacts to allow multiple working, but the 745's coupler has no contacts and the coupler is only used for rescuing, even though they are the same manufacturer and operator.

It would be interesting though, 2 745s in passenger service, 24 carriages

 

[edwin_m]

Adding on, rescued trains are "dragged" and unpowered - the locomotive provides all the power and the unit is out of service. Multiple working allows all (or most) equipment on all units to function, such as lighting, pantographs, engines, motors, brakes. Software, electrics (such as voltage), and couplers are all individual issues between units. Take a look at most units fitted with scharfenberg couplers, the electrical contacts are often different.

An example is the 755 and 745. The 755s are fitted with electrical contacts to allow multiple working, but the 745's coupler has no contacts and the coupler is only used for rescuing, even though they are the same manufacturer and operator.

You need some way of operating the brakes otherwise a coupling failure could lead to disaster.

 

[saismee]

It would be interesting though, 2 745s in passenger service, 24 carriages

The longest (IIRC) was 745 + 755/4, though it was a rescue.

You need some way of operating the brakes otherwise a coupling failure could lead to disaster.

I believe the coupler itself has hoses? Someone more knowledgeable of Dellner couplers (or couplers/brakes in general, I'm not well-versed) would need to confirm.

 

[InkyScrolls]

There are specific rules relating to moving a unit with car isolated brakes - it's too late for me to go into now but suffice to say it's possible. As for Dellner couplers (and others), hoses are indeed used if coupling in multiple isn't an option.

 

[61653 HTAFC]

Whilst lots of later BR types can work in multiple (Sprinters and Pacers for example) and by the end BR had settled on just a few standards, this wasn't always the case. First generation DMUs had several different multiple working systems (designated with a colour and shape, e.g. Blue Star) so incompatibility isn't just a curse of the modern era.

 

[norbitonflyer]

Whilst lots of later BR types can work in multiple (Sprinters and Pacers for example) and by the end BR had settled on just a few standards, this wasn't always the case. First generation DMUs had several different multiple working systems (designated with a colour and shape, e.g. Blue Star) so incompatibility isn't just a curse of the modern era.

You are thinking of "blue square", the coupling code for all 1st generation DMUs except the diesel hydraulics of classes 125 (orange star), the Scottish InterCity units of Class 126 (white circle), and the early "lightweight" designs numbered in the 79xxx range (red triangle and yellow diamond), and the three class 129s built to work with them. Diesel hydraulic Classes 113 and 127 were later given a separate coupling code as it was found that, although designed to work with DMMUs, there were problems with driving technique when a hydraulic unit was leading a mechanical one.

Blue star was a loco coupling code, and became the defacto standard for first generation diesels - classes 15, 20, 23, 24-27, 33, 37, 40, and 44-46, and later members of classes 17, 21 and 31 all being compatible.
The "red circle" classes (16, 28, 29 and earlier members of classes 21 and 31) and "red diamond" (early class 17s) were all withdrawn early as non-standard, as were the various diesel hydraulic classes (three different coupling codes).
However, there was never a time when "blue star" or "blue square" were universal - some 127s hung on as parcels units well into the Sprinter era, whilst there were still several red circle locos around when the first "orange square" class 50s appeared, and Classes 47, 52 and 55 were not fitted for working in multiple at all. The "Red diamond" symbol was re-used for classes 56 and 58.

 

[61653 HTAFC]

You are thinking of "blue square", the coupling code for all 1st generation DMUs except the diesel hydraulics of classes 125 (orange star), the Scottish InterCity units of Class 126 (white circle), and the early "lightweight" designs numbered in the 79xxx range (red triangle and yellow diamond), and the three class 129s built to work with them. Diesel hydraulic Classes 113 and 127 were later given a separate coupling code as it was found that, although designed to work with DMMUs, there were problems with driving technique when a hydraulic unit was leading a mechanical one.

Blue star was a loco coupling code, and became the defacto standard for first generation diesels - classes 15, 20, 23, 24-27, 33, 37, 40, and 44-46, and later members of classes 17, 21 and 31 all being compatible.
The "red circle" classes (16, 28, 29 and earlier members of classes 21 and 31) and "red diamond" (early class 17s) were all withdrawn early as non-standard, as were the various diesel hydraulic classes (three different coupling codes).
However, there was never a time when "blue star" or "blue square" were universal - some 127s hung on as parcels units well into the Sprinter era, whilst there were still several red circle locos around when the first "orange square" class 50s appeared, and Classes 47, 52 and 55 were not fitted for working in multiple at all. The "Red diamond" symbol was re-used for classes 56 and 58.

Thanks for the correction and clarification, yes "blue square" was what I was thinking of. I did almost write "blue circle" until I remembered that was a brand of cement!
Your final paragraph is pretty much the point I was trying to make: that this idea that different classes not being able to work in multiple is not simply a consequence of modern units having a load of computers on board.