Pantograph issues on Pendolino

[rockford]

A while back I was travelling on a Pendolino into Euston when the interior lighting suddenly failed. The train manager came over the intercom and apologised for the situation, asked passengers not to use the toilets and said that we were running in (what sounded like) "de-group mode".
I may have heard this completely wrong though...
What is this mode and why would a train have to run like this?
Thanks!

 

[MCR247]

I doubt it would be a pantograph issue as it carried on running..?

 

[hairyhandedfool]

No reason why a pan can't be lowered on the move.

 

[MCR247]

No, but the train carried on as normal to Euston by the sounds off minus lights etc

 

[Peter Mugridge]

How far out of Euston was this? It's surprising how far it is possible to coast if there is a clear road ahead.

 

[rockford]

How far out of Euston was this? It's surprising how far it is possible to coast if there is a clear road ahead.

It was a fair way out. I can't remember where we were now, but it must have been about 15 minutes worth of travelling time. The train was definitely running under it's own power.
And it was definitely a pantograph issue as the TM mentioned swapping from the front pan to the rear, but that was tried and also failed. That was when this "de-group mode" was mentioned.

 

[Peter Mugridge]

15 minutes would be somewhere between Watford and Harrow wouldn't it?

Entirely possible to coast from there, though you say it was definitely under power, presumably meaning you could hear and feel the traction motors powering?

 

[Pumbaa]

It's 15 mins WFJ - EUS on 350 timings, not sure on 390.

Western champion or Respite, your knowledge is called for!

 

[Lampshade]

It's 15 mins WFJ - EUS on 350 timings, not sure on 390.

22m according to the 2035 MAN - EUS service, most of which is probably recovery time.

 

[O L Leigh]

I doubt that's a pan problem but more of an on-board power supply problem. Swapping pans on a Cl390 could simply be one way of attempting to rectify the fault rather than any indication of issues with the pantograph itself. The fact that it didn't work seems to exonerate the pan.

Most times you wouldn't know there was an issue with the pan until the ADD operates or you observe unusual movement in the OLE or hear unusual noises. In that case you must drop the pan, stop immediately and inform the signaller ("Drop - Stop - Box", as we are taught). This a Rule Book requirement so cannot be circumvented by TOC policy. If the train didn't stop then it almost certainly wasn't a problem with the pan.

It sounds like the train suffered some sort of failure relating to either the main transformer or the on-board power distribution systems, as clearly the only circuits affected were the non-vital ones. Had the main supply failed the train would have stopped much more quickly, either under the control of the driver or automatically when the main air pressure dropped too low. I don't know anything about the Cl390s to speculate further on the precise nature of the failure, though.

O L Leigh

 

[Erniescooper]

Only have a limited knowledge of Pendolino myself, but it sounds like a Auxilliary Converter failure and the lights going off would be part of a load shed for the failure.

 

[captainbigun]

Only have a limited knowledge of Pendolino myself, but it sounds like a Auxilliary Converter failure and the lights going off would be part of a load shed for the failure.

That would be my take too.

 

[Peter301184]

Only have a limited knowledge of Pendolino myself, but it sounds like a Auxilliary Converter failure and the lights going off would be part of a load shed for the failure.

Also agree this is what it sounds like.

 

[whhistle]

And what the hell, I'll agree too!

 

[rockford]

Thanks for all the responses. We did come to a standstill at one point, and then began moving again, hence knowing the train was moving under it's own steam.
From this, it was obviously not a complete failure, so your suggestions seem to be on the money.
Thank you.

 

[western Champion]

A Pendolino is in simple terms two half trains joined together, you will notice that half way down the train the fire extinguishers are in the opposite vestibule, outside the brake indicators are transposed to the other end of the vehicle etc etc etc.

Each half has two auxiliary converters, if both converters fail and lock out then that half is essentially electrically dead (loss of lights, HVAC etc). The train can continue but it means the good half is pushing or pulling the bad half with all the performance issues that entails.

Normally the maintenance control would ask the driver to stop en route and do a full reset (drop the pan, trip the auxiliaries, wait thirty seconds, reset auxiliaries and raise the pan) but in the case being discussed providing I had sufficient speed I would coast to Euston. It is easy to coast from Tring downhill all the way to Euston, they encourage it as "green" driving if running on time or early.