Class 390 Pendolino PTSRMB

[Class 323221]

Hello everyone,

A short question:

I was looking into the formation of the Class 390. I am a bit confused by the PTSRMB. I am under the impression that it stands for 'Pantograph Trailer Standard Resteraunt Motor Buffet' or 'Pantograph Standard Buffet'. This seems a bit weird as I thought there weren't motors in the pantograph car and the 'T' and 'M' also suggest that I am wrong as one is 'trailer' and the other 'motor'. Would anyone be able to help me to understanding this car?

Thank you everyone and have a good evening.

 

[D1537]

I believe that PTSRMB stands for Pantograph Trailer Standard Restaurant Miniature Buffet, like the RMB in hauled coaches.

 

[Class 323221]

I believe that PTSRMB stands for Pantograph Trailer Standard Restaurant Miniature Buffet, like the RMB in hauled coaches.

Thank you. That would make more sense then. I didn't think that Pantograph cars have motors. At least not usually.

 

[NSEWonderer]

Thank you. That would make more sense then. I didn't think that Pantograph cars have motors. At least not usually.

I assume this is in regards to 390s and not in general for all trains?

 

[norbitonflyer]

Thank you. That would make more sense then. I didn't think that Pantograph cars have motors. At least not usually.

Aventras (classes 345/710/720/730) do, and so do/did BR-era units (classes 302-305,308-312, 316-325, 365, 506)

 

[Efini92]

Hello everyone,

A short question:

I was looking into the formation of the Class 390. I am a bit confused by the PTSRMB. I am under the impression that it stands for 'Pantograph Trailer Standard Resteraunt Motor Buffet' or 'Pantograph Standard Buffet'. This seems a bit weird as I thought there weren't motors in the pantograph car and the 'T' and 'M' also suggest that I am wrong as one is 'trailer' and the other 'motor'. Would anyone be able to help me to understanding this car?

Thank you everyone and have a good evening.

You are correct that the pantograph car doesn’t have traction motors.

 

[43096]

Aventras (classes 345/710/720/730) do, and so do/did BR-era units (classes 302-305,308-312, 316-325, 365, 506)

323 and 365 don't/didn't.

 

[Class 323221]

I assume this is in regards to 390s and not in general for all trains?

I meant as in a general for all trains, however it appears that I have been corrected on that. I thought it was a general thing that Pantograph cars did not feature a motor but apparently my local line has stock that do.

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Aventras (classes 345/710/720/730) do, and so do/did BR-era units (classes 302-305,308-312, 316-325, 365, 506)

Do you know if there is any reason for the Aventras to have motors in all cars? Especially for a three car Multiple Unit, I don't see why it is needed.

== Doublepost prevention - post automatically merged: 17 Nov 2025 ==

You are correct that the pantograph car doesn’t have traction motors.

Ah. That makes more sense then. Thank you.

== Doublepost prevention - post automatically merged: 17 Nov 2025 ==

323 and 365 don't/didn't.

Yes, I remember that the 323s didn't, you could just hear a hum from the PTSO if you were on the outside.

 

[NSEWonderer]

I meant as in a general for all trains, however it appears that I have been corrected on that. I thought it was a general thing that Pantograph cars did not feature a motor but apparently my local line has stock that do.

== Doublepost prevention - post automatically merged: 17 Nov 2025 ==


Do you know if there is any reason for the Aventras to have motors in all cars? Especially for a three car Multiple Unit, I don't see why it is needed.

== Doublepost prevention - post automatically merged: 17 Nov 2025 ==


Ah. That makes more sense then. Thank you.

== Doublepost prevention - post automatically merged: 17 Nov 2025 ==


Yes, I remember that the 323s didn't, you could just hear a hum from the PTSO if you were on the outside.

Aventras (classes 345/710/720/730) do, and so do/did BR-era units (classes 302-305,308-312, 316-325, 365, 506)

Was Going to say, our 701s definitely have motorised pantograph cars, so had to be sure I wasn't going mad.

As for why they have motorised pantograph cars, why not? Older trains didn't have it, most likely due to how restrictive the technology was back then and the complex amount of work needed to fit all that equipment into one car, where as technology has become a lot better, equipment smaller and more efficient.

 

[Nym]

And of course historically the motors were in the same car as the transformer to reduce the length of thick power cables.

 

[D365]

Do you know if there is any reason for the Aventras to have motors in all cars? Especially for a three car Multiple Unit, I don't see why it is needed.

There are no three car Aventras in production. But, considering the Class 345 for example, each vehicle has one motored bogie and one trailer bogie.

 

[DaveyJones]

There are no three car Aventras in production. But, considering the Class 345 for example, each vehicle has one motored bogie and one trailer bogie.

730/0 begs to differ I have no idea on how they're motored though

 

[D365]

730/0 begs to differ I have no idea on how they're motored though

The replacement of Class 323s somehow slipped my mind.

This post suggests that Class 730 has the same 2’Bo (trailer + motored) bogie arrangement on each coach. Although there doesn’t seem to be a consensus on whether the motored bogie is at the No.1 (cab) or No.2 (gangway) end.

 

[hexagon789]

There are no three car Aventras in production. But, considering the Class 345 for example, each vehicle has one motored bogie and one trailer bogie.

345s are actually quite complex in their traction arrangements having both half-motored cars (2'Bo), fully motored cars (Bo'Bo) as well as one trailer car (2'2) in the centre - with 20 traction motors in all across a set.

The arrangement you describe does apply to the 730s though, where each vehicle is motored on one bogie.

730/0 begs to differ I have no idea on how they're motored though

Each vehicle has one motored and one un-motored bogie - a 2'Bo arrangement.

The replacement of Class 323s somehow slipped my mind.

This post suggests that Class 730 has the same 2’Bo (trailer + motored) bogie arrangement on each coach. Although there doesn’t seem to be a consensus on whether the motored bogie is at the No.1 (cab) or No.2 (gangway) end.

730s have the un-motored bogie under the cab.

 

[MCR247]

The replacement of Class 323s somehow slipped my mind.

This post suggests that Class 730 has the same 2’Bo (trailer + motored) bogie arrangement on each coach. Although there doesn’t seem to be a consensus on whether the motored bogie is at the No.1 (cab) or No.2 (gangway) end.

730s have the un-motored bogie under the cab.

I believe earlier Electostar like 375s and 377s also have an unmotored bogie under the cab

 

[Falcon1200]

As for why they have motorised pantograph cars, why not? Older trains didn't have it,

The Glasgow Blue Trains, Class AM3 and later 303, dating from 1960, did! The motorised pantograph car was the centre vehicle.

 

[D365]

345s are actually quite complex in their traction arrangements having both half-motored cars (2'Bo), fully motored cars (Bo'Bo) as well as one trailer car (2'2) in the centre - with 20 traction motors in all across a set.

Thanks for clarifying. This makes the most sense as it provides symmetry if Class 345 units are ever shortened back to 7 cars, or lengthened to 11 cars.

Additionally, I understand that the leading bogie at each cab is unbraked, to allow for precise measurement of distance travelled.

The arrangement you describe does apply to the 730s though, where each vehicle is motored on one bogie.


Each vehicle has one motored and one un-motored bogie - a 2'Bo arrangement.


730s have the un-motored bogie under the cab.

I suspected that this would be the case in order to mirror the Class 345 approach.

The Glasgow Blue Trains, Class AM3 and later 303, dating from 1960, did! The motorised pantograph car was the centre vehicle.

Same with Class 318/320.

 

[hexagon789]

Thanks for clarifying. This makes the most sense as it provides symmetry if Class 345 units are ever shortened back to 7 cars, or lengthened to 11 cars.

Exactly, because then the performance is unaffected by lengthening.

Additionally, I understand that the leading bogie at each cab is unbraked, to allow for precise measurement of distance travelled.

I believe it's just the outermost axles at each end, but is for exactly the reason you give.

 

[NSEWonderer]

The Glasgow Blue Trains, Class AM3 and later 303, dating from 1960, did! The motorised pantograph car was the centre vehicle.

Older was a broad wording.