some bloke
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extract from an Alstom presentation.
Would anyone like to guess how fast the train would have entered Euston without braking, from the first graph?
extract from an Alstom presentation.
Would that not cause problems next time you want power, as you now have no power with which to raise it again? Or is there some mechanism to get round that?
How do you create the air pressure if you have no power, though?It's air pressure.
How do you think they are raised when a unit has been shut down?
How do you create the air pressure if you have no power, though?
It’s a bit of an irrelevance though, admittedly, as the loss of air pressure will mean that the pan will have dropped of its own accord by that stage anyway!
That’s my point, really! A fair point about preserving the batteries to allow normal working to be resumed when the power supply is restored, but would drivers normally consider this vs keeping systems on the train running for as long as possible (for the passengers’ benefit)? Are there any instructions to that effect?There's an auxiliary compressor that is powered by 110v battery supply for initial power-up. As per my post above, that's no good if the driver has allowed the batteries to become flat.
One thing which ranks highly on my list of railway oddities I’ve witnessed was watching a class 385 being ‘jump started’ with a boost pack to get enough charge in the batteries to allow the aux compressor to run...There's an auxiliary compressor that is powered by 110v battery supply for initial power-up. As per my post above, that's no good if the driver has allowed the batteries to become flat.
One thing which ranks highly on my list of railway oddities I’ve witnessed was watching a class 385 being ‘jump started’ with a boost pack to get enough charge in the batteries to allow the aux compressor to run...
That’s my point, really! A fair point about preserving the batteries to allow normal working to be resumed when the power supply is restored, but would drivers normally consider this vs keeping systems on the train running for as long as possible (for the passengers’ benefit)? Are there any instructions to that effect?
One thing which ranks highly on my list of railway oddities I’ve witnessed was watching a class 385 being ‘jump started’ with a boost pack to get enough charge in the batteries to allow the aux compressor to run...
Surely, if a 185 automatically shuts down one of its engines, then it will restart it automatically, too, irrespective of whether the train is in motion or not. No?
That’s my point, really! A fair point about preserving the batteries to allow normal working to be resumed when the power supply is restored, but would drivers normally consider this vs keeping systems on the train running for as long as possible (for the passengers’ benefit)? Are there any instructions to that effect?
Most probably. I just can't work out how an engine would be affected starting up while the train as at speed against it being stationary. What's different other than the speed of the train?
The engine on a 185 will remain at idle if started on the move as the Driver will need to select neutral and then forward to engage the transmission relays on the restarted vehicle.
And I presume you can't select neutral while on the move? (I believe you can't on a variety of classes.)
Nope. I haven't tried it but I'm sure the switch is locked to prevent that but at very least I would expect a brake application as happens with 14x and 15x.
I did suggest to the Hitachi fitter that they might have been sensible to install a last resort bicycle pump...I borrowed a Corkerhill 156 to blow up a 350 for pantograph air when it's aux compressor failed a few months ago!
I did suggest to the Hitachi fitter that they might have been sensible to install a last resort bicycle pump...
The "break"?I like the break very adaptive, on training we hit the platform ramp at gypsy hill doing 45 100% break and had to take it of to stop at the 8 car mark.
Don't you have to try emergency braking in type training? I would have expected all likely performance elements to be covered.With these nice 700's I drive 60%/60% no need to go more than that ever. Under fcc any braking over 80mph had to be a full service step 3 application. Now we have no steps just feeling what we need, they certainly stop on the dime in 100%. Not tried emergency yet so not sure how that feels.
Don't you have to try emergency braking in type training?
I’ve never come across it though I know the Woodhead EM1 and EM2 locos had hand pumps to raise the pans.
However, if you put the reverser into neutral, it would disable the deadman's and given Ireland's generally flat topography, you could coast for miles and save your muscles!
Supposedly back in the 50s/60s when many services in Ireland were worked by AEC built railcars, they had a design feature where the dead man's handle had to be pushed down with one hand all of the time or else the brakes would kick in. However, if you put the reverser into neutral, it would disable the deadman's and given Ireland's generally flat topography, you could coast for miles and save your muscles!
73s had a car footpump to pump the shoes down if you had flat batteries if over a juice railSome units do have a manual pump of some kind for that purpose, don't they?
you had to have the gear sector in direction off travel [no neutral ]with deadmans handle or overide button on secondmans side by the window depressed to stop brakes applying and prevent the dogs shattering through lack off air pressure them skipping in and out through vibrationI believe the first generation BR DMUs were like that, the throttle had to be held down or the vacuum would be destroyed. Not sure if the reverser could be set to neutral to negate that though.
you had to have the gear sector in direction off travel [no neutral ]with deadmans handle or overide button on secondmans side by the window depressed to stop brakes applying and prevent the dogs shattering through lack off air pressure them skipping in and out through vibration