Hull Trains - OHL to Diesel Changeover

[Max]

A slightly random observation, but I noticed when travelling on a Hull Trains 802 for the first time earlier this week that the OHL to diesel changeover takes place at Doncaster, whereas I'm pretty sure LNER 800s on the direct Hull do the changeover on the move closer to Temple Hirst. Can anybody explain why this is? It does seem a little surprising and a rather pointless to run on diesel for an extra 15-20 miles when electric is available.

 

[GRALISTAIR]

Informed Sources Law 1 possibly?

‘Informed Sources’ Laws 2020

Here’s your handy guide, plus some background...

www.keymodernrailways.com

First Law ‘Never assume railways are rational organisations’

 

[Lewlew]

Is it just that different companies have different policies? Similar to the West London Line where Southern stop at a signal, change from 3rd rail to Overhead and London Overground do it on the move even though they use a very similar train.

 

[800001]

Most likely Hull just don't have the automatic power change over software in use or on there train?

 

[Val3ntine]

Is it just that different companies have different policies? Similar to the West London Line where Southern stop at a signal, change from 3rd rail to Overhead and London Overground do it on the move even though they use a very similar train.

As london overground uses a single unit there’s only 1 pan, so raising it on the move at a designated location ensures it will be under the wires. Southern however using 2 units with 2 pans there’s a risk not raising it at the very last point that the rear unit’s pan could miss the start of the wires and cause an ADD activation, or worse strike the very low A40 bridge that is just at the rear of the wires commencing.
Also Pans need to be raised before the signal otherwise units must stop so that trains can be routed around the failed unit using the bi-directional working to avoid blocking the whole WLL. Overground units can get away with raising on the move and coming to a stop before the signal if any fault is spotted, southern units dont have that space.

 

[Ianno87]

As london overground uses a single unit there’s only 1 pan, so raising it on the move at a designated location ensures it will be under the wires. Southern however using 2 units with 2 pans there’s a risk not raising it at the very last point that the rear unit’s pan could miss the start of the wires and cause an ADD activation, or worse strike the very low A40 bridge that is just at the rear of the wires commencing.
Also Pans need to be raised before the signal otherwise units must stop so that trains can be routed around the failed unit using the bi-directional working to avoid blocking the whole WLL. Overground units can get away with raising on the move and coming to a stop before the signal or any fault is spotted, southern units dont have that space.

And both operators use different types of train.

 

[Val3ntine]

And both operators use different types of train.

That too . Maybe a simpler and quicker explanation

 

[LNW-GW Joint]

Most likely Hull just don't have the automatic power change over software in use or on there train?

That would be very surprising as 802s are in use with GWR and TPE as well as HT, and I'm fairly sure they can switch on the move.
Otherwise the OHLE extension from Colton Jn to Church Fenton will remain unused.

 

[800001]

That would be very surprising as 802s are in use with GWR and TPE as well as HT, and I'm fairly sure they can switch on the move.
Otherwise the OHLE extension from Colton Jn to Church Fenton will remain unused.

TPE change over stationary at York Station, where as Lner 1E30/1W02 both change over on the move near Colton Junction

 

[LNW-GW Joint]

TPE change over stationary at York Station, where as Lner 1E30/1W02 both change over on the move near Colton Junction

But the whole point of wiring to Church Fenton is to extend electric operation towards Leeds.
Not much point if TPE are still going to change over while stationary at York.
The IEP spec required changeover on the move.
I doubt that capability has been removed on the later 80x bi-mode builds.

 

[800001]

But the whole point of wiring to Church Fenton is to extend electric operation towards Leeds.
Not much point if TPE are still going to change over while stationary at York.
The IEP spec required changeover on the move.
I doubt that capability has been removed on the later 80x bi-mode builds.

I didn't diasagree, I stated what they do at the moment, wiring extension is a few years a way, plenty of time for TPE to change policy

 

[norbitonflyer]

Do any Hull services run via Goole?

 

[yorkie]

Do any Hull services run via Goole?

Only if diverted

 

[tbtc]

HT and TPE could just be doing this at stations for a period until they are confident that drivers are remembering to do the changeover (given that it's not something they'll have been doing until fairly recently) - given the potential costs if a train were to try running beyond the wires without having turned the diesel engines on?

I don't know if other TOCs were changing power "on the move" (rather than when sat at stations), but I could see sense in taking precautions when introducing new technology.

 

[43066]

I’ve been told that diesel engines on 8XXs need to be warmed up by running them for a period before the changeover can occur (when going from electric to diesel obviously). Any truth in this?

 

[Mag_seven]

I’ve been told that diesel engines on 8XXs need to be warmed up by running them for a period before the changeover can occur (when going from electric to diesel obviously). Any truth in this?

That is definitely my experience on the GWR Class 800s

 

[221129]

The IEP spec required changeover on the move.

The TPE 802s aren't part of the IEP and are not IEP spec.

 

[800001]

I’ve been told that diesel engines on 8XXs need to be warmed up by running them for a period before the changeover can occur (when going from electric to diesel obviously). Any truth in this?

Correct, the engines have to be a certain temperature before they can take power.

On auto power change over, the train will automatically pre heat, for a change in station, drivers will preheat at a certain tine before they change over.

 

[Wilts Wanderer]

It may be that the Hull Trains risk assessment decided that because of the possibility of using the Goole diversionary route, it was safest to standardise Doncaster as the mandatory power change to remove a potential human error factor?

 

[43066]

That is definitely my experience on the GWR Class 800s

Correct, the engines have to be a certain temperature before they can take power.

On auto power change over, the train will automatically pre heat, for a change in station, drivers will preheat at a certain tine before they change over.

Thanks both.

Presumably if the pre warming doesn’t happen for any reason, due to fault/forgetfulness, the train will need to stop to allow it to take place?

 

[Max]

Thanks all for the useful insight. I did the journey in the other direction today and the changeover also happened in the platform at Doncaster rather than at Temple Hirst. Given the "forgetting" issue isn't as significant heading southbound, I can only assume it is just a Hull Trains policy not to do this on the move, or there is a technical reason. The "Goole factor" does also seem potentially relevant.

 

[Dren Ahmeti]

Thanks both.

Presumably if the pre warming doesn’t happen for any reason, due to fault/forgetfulness, the train will need to stop to allow it to take place?

No. From my understanding, if the pan is lowered by the point required, it will not trip the “last chance” ADD balise located just after the changeover signs, and so the train will just coast until the engines are warmed enough.

 

[swt_passenger]

The TPE 802s aren't part of the IEP and are not IEP spec.

However in the case of TPE we know from previous discussions that Network Rail have fitted automatic changeover equipment at Chathill and Longniddry specifically to allow moving changeover either side of the limited power supply area in the borders. It would be surprising if NR did that if the trains aren’t capable...

 

[Starmill]

However in the case of TPE we know from previous discussions that Network Rail have fitted automatic changeover equipment at Chathill and Longniddry specifically to allow moving changeover either side of the limited power supply area in the borders. It would be surprising if NR did that if the trains aren’t capable...

Indeed! Every time it's brought up, it's mentioned that the difference is one of internal company policy and not one of a particular technical limitation.

 

[MotCO]

Are there trackside signs to advise drivers to raise/lower pans and warm up the engines?

 

[Class 170101]

It may also be the wiring in the Temple Hirst area can't take changeover on the move. On GWR where it takes place there is higher tensioning so the process of raising / lowering the pantograph doesn't bring down the wires.

 

[800001]

Thanks both.

Presumably if the pre warming doesn’t happen for any reason, due to fault/forgetfulness, the train will need to stop to allow it to take place?

If it is close to running out of wires then yes it would need

It may also be the wiring in the Temple Hirst area can't take changeover on the move. On GWR where it takes place there is higher tensioning so the process of raising / lowering the pantograph doesn't bring down the wires.

Wires must be ok, as Lner do it on move at about 70mph I think

 

[Domh245]

If it is close to running out of wires then yes it would need

That's surprising. I would have thought it preferable to take the minor (maybe .5hrs off the engine's life if it was near zero) hit to the engine life than stopping the train, completing the preheating and accelerating away again. Hell, you could just coast the train until they're prewarmed, or even limit engine output until warmed (in the same way you shouldn't accelerate hard in a recently-started car)

 

[800001]

That's surprising. I would have thought it preferable to take the minor (maybe .5hrs off the engine's life if it was near zero) hit to the engine life than stopping the train, completing the preheating and accelerating away again. Hell, you could just coast the train until they're prewarmed, or even limit engine output until warmed (in the same way you shouldn't accelerate hard in a recently-started car)

Comment isnt to be taken literally, am pretty sure of change over hadn't happened as planned tgat drivers have preplanned routines they must follow ie stop, long before Wires run out.

As for starting engine before temp is OK, can't do anything with the engine with out Hitachi Maintenence Controllers permission

 

[Domh245]

Comment isnt to be taken literally, am pretty sure of change over hadn't happened as planned tgat drivers have preplanned routines they must follow ie stop, long before Wires run out.

As for starting engine before temp is OK, can't do anything with the engine with out Hitachi Maintenence Controllers permission

I'm sure that they would stop whilst still on the wires, but it's the stopping at all that irks me. I don't know how many high speed transitions there are, but delaying the train because the engine is cold with consequent risks of snowballing delay later down the line just doesn't seem the right thing to do. It does feel a bit horse before cart here, the railway is run for the passenger's benefit, not for Hitachi's convenience