Why does the 357 accelerate almost 2x as fast as every other electrostar?

[357]

Personally I don't know why they would be isolated at all - either by software or by hardware

Yeah, for more powerful units gradient will make less difference.
I did hear someone say 357s power to weight is better than the other electrostars, that would aid takeoff massively we can all agree

377 4 car is 173t, 357 4 car is 157t

 

[SolomonSouth]

Personally I don't know why they would be isolated at all - either by software or by hardware


377 4 car is 173t, 357 4 car is 157t

But 357 4 car is only 1600 hp and 357 4 car is like 2000 hp

 

[357]

But 357 4 car is only 1600 hp and 357 4 car is like 2000 hp

There's more to performance than a KW to HP conversion.

The actual amount of power used is controlled by the onboard systems.

Even if a 357 is slightly faster, I doubt it is very noticeable or anything like the double speed you referred to earlier

 

[SolomonSouth]

There's more to performance than a KW to HP conversion.

The actual amount of power used is controlled by the onboard systems.

Even if a 357 is slightly faster, I doubt it is very noticeable or anything like the double speed you referred to earlier

I did hear once that 377s/379s/387s are power limited at the lower speed so that past 60, they have better acceleration. The 357s apparently aren't limited at lower speeds but tractive effort falls away more, if anyone could confirm?
I will time them of course. Might take a while though due to irl things.
Maybe I should edit the thread title and take the 2x out lol

 

[theking]

That 378 is not taking full power.

Also ac is considerably faster than dc.

 

[Railperf]

Given a full power start - on a dry rail and on level track the various AC variants of Electrostars do 0 to 60mph from 44 to 50 seconds.
On 3rd rail DC acceleration is similar to around 30mph..but after that, acceleration is much slower than AC due to the units being programmed to limit current draw from the 3rd rail supply. 2 x units coupled together will be slower than a single 4-car as the software limits the current draw per unit further.
I have seen 0 to 60mph in 44s for both 357 and 379s. AC power of course.

 

[Bald Rick]

Given a full power start - on a dry rail and on level track the various AC variants of Electrostars do 0 to 60mph from 44 to 50 seconds.
On 3rd rail DC acceleration is similar to around 30mph..but after that, acceleration is much slower than AC due to the units being programmed to limit current draw from the 3rd rail supply. 2 x units coupled together will be slower than a single 4-car as the software limits the current draw per unit further.
I have seen 0 to 60mph in 44s for both 357 and 379s. AC power of course.

Well that’s definitive! Thank you.

 

[SolomonSouth]

Given a full power start - on a dry rail and on level track the various AC variants of Electrostars do 0 to 60mph from 44 to 50 seconds.
On 3rd rail DC acceleration is similar to around 30mph..but after that, acceleration is much slower than AC due to the units being programmed to limit current draw from the 3rd rail supply. 2 x units coupled together will be slower than a single 4-car as the software limits the current draw per unit further.
I have seen 0 to 60mph in 44s for both 357 and 379s. AC power of course.

Thank you! But why is the vid on YT for the 379 53 secs?
Saves me going to time it at least! I will still have to do a 376 and 378 ofc.

Well that’s definitive! Thank you.

I agree. Didn't know this guy had also timed 357s

 

[Bald Rick]

Thank you! But why is the vid on YT for the 379 53 secs?

As has been said up thread several times, any combination of different gradient / weather / rail conditions / signalling conditions / unit health / driving style.

 

[SolomonSouth]

As has been said up thread several times, any combination of different gradient / weather / rail conditions / signalling conditions / unit health / driving style.

Tbf yes. Sorry my error, but the gradient was pretty level in the video with good weather, so it was maybe the unit being poor or the driver.

 

[Railperf]

Tbf yes. Sorry my error, but the gradient was pretty level in the video with good weather, so it was maybe the unit being poor or the driver.

Which video are you refering to?

 

[SolomonSouth]

Which video are you refering to?

This one

 

[Bald Rick]

Tbf yes. Sorry my error, but the gradient was pretty level in the video with good weather, so it was maybe the unit being poor or the driver.

1:270 at the start, before easing off.

And no point giving it the beans as most Stansted expresses have pathing time approaching Broxbourne or Harlow, so they will just catch up with the previous train earlier.

 

[paul1609]

As has been said up thread several times, any combination of different gradient / weather / rail conditions / signalling conditions / unit health / driving style.

On DC you can add to that the location, 375s and 377s are noticably faster on the SEML where the power supply was reinforced for the Channel Tunnel traffic. I believe that the average voltage is higher. Apparently when the power upgrades were introduced the service speed of the 4 CEPS increased by as much as 10 mph on some up hill sections.

 

[SolomonSouth]

On DC you can add to that the location, 375s and 377s are noticably faster on the SEML where the power supply was reinforced for the Channel Tunnel traffic. I believe that the average voltage is higher. Apparently when the power upgrades were introduced the service speed of the 4 CEPS increased by as much as 10 mph on some up hill sections.

Woah. That's loads

1:270 at the start, before easing off.

And no point giving it the beans as most Stansted expresses have pathing time approaching Broxbourne or Harlow, so they will just catch up with the previous train earlier.

Ok. How do you calculate that the graident is 1:270 (uphill or downhill btw?)

 

[Darandio]

Ok. How do you calculate that the graident is 1:270 (uphill or downhill btw?)

Look at a gradient profile for the location in question.

 

[Railperf]

This one

Yeah.. The driver applied power more gradually hence the slower time. I have recorded faster times with a non video GPS device. I don't always record videos.

 

[SolomonSouth]

Look at a gradient profile for the location in question.

What gradient profile? Are they available online somewhere? If so, please show.

Yeah.. The driver applied power more gradually hence the slower time. I have recorded faster times with a non video GPS device. I don't always record videos.

Oh ok so thats why you haven't uploaded for over a year.
What app do you use BTW? It's way more accurate than my vidometer app, would be appreciated if you could tell me

 

[Darandio]

What gradient profile? Are they available online somewhere? If so, please show.

They can be obtained from various places. In terms of online here is one resource to get you started. http://www.railwaydata.co.uk/linefiles/

Specifically for the location in the video it would be this one. http://www.railwaydata.co.uk/linefiles/route/?ELR=BGK

 

[Railperf]

What gradient profile? Are they available online somewhere? If so, please show.

Oh ok so thats why you haven't uploaded for over a year.
What app do you use BTW? It's way more accurate than my vidometer app, would be appreciated if you could tell me

I use the Ian Allan book - British Rail Mainline Gradient profiles. In this it shows a short section of 1 in 490 uphill - becoming level and then uphill just north of Northumberland Park 1 in 864 to a point just north of the old angel Road station and level again for about 1.5 miles.
Enfield lock Northbound and Waltham Cross southbound are also level for a mile. Waterbeach southbound is also level

For 357,s the level stretch is leigh on Sea towards Benfleet. and Barking towards Upminster.

Going back to one of the original posts about 465 from Teynham - according to the gradient profile book that is 1 in 200 downhill increasing to 1 in 140.
What we try to do in those situations is balance a downhill time on a 1 in 200 with an uphill time on a similar gradient.

The video app i used in the Class 379 video was a Garmin Virb Ultra 30 camera. The camera records GPS data and the two are synchronised using a Garmin video editing app on a PC

A better solution is Harrys Lap timer app for Android - combined with a Dual XGPS Bluetooth GPS receiver. The app will record the video and GPS together. This is processed on the phone. No PC needed. And the XGPS device provides a better reception than the Garmin GPS chip.
The XGPS is a more accurate and dynamic GPS device than most phone GPS chipsets too - providing a reading every 0.1 seconds.

That was the combination I used to record the HST video here:

 

[SolomonSouth]

I use the Ian Allan book - British Rail Mainline Gradient profiles. In this it shows a short section of 1 in 490 uphill - becoming level and then uphill just north of Northumberland Park 1 in 864 to a point just north of the old angel Road station and level again for about 1.5 miles.
Enfield lock Northbound and Waltham Cross southbound are also level for a mile. Waterbeach southbound is also level

For 357,s the level stretch is leigh on Sea towards Benfleet. and Barking towards Upminster.

Going back to one of the original posts about 465 from Teynham - according to the gradient profile book that is 1 in 200 downhill increasing to 1 in 140.
What we try to do in those situations is balance a downhill time on a 1 in 200 with an uphill time on a similar gradient.

The video app i used in the Class 379 video was a Garmin Virb Ultra 30 camera. The camera records GPS data and the two are synchronised using a Garmin video editing app on a PC

A better solution is Harrys Lap timer app for Android - combined with a Dual XGPS Bluetooth GPS receiver. The app will record the video and GPS together. This is processed on the phone. No PC needed. And the XGPS device provides a better reception than the Garmin GPS chip.
The XGPS is a more accurate and dynamic GPS device than most phone GPS chipsets too - providing a reading every 0.1 seconds.

That was the combination I used to record the HST video here:

Ok. Thanks. So I could try to time a 465/2 or 465/9 on an uphill or preferably level track. But not sure where you can reach 0-75 on level track for a 465/9.
Greenhithe towards Dartford allows for 70mph, for the Gravesend-Victoria services, although /9s rarely run those. Northfleet-Gravesend is 70mph too but I believe that is a falling gradient.

 

[Railperf]

Ok. Thanks. So I could try to time a 465/2 or 465/9 on an uphill or preferably level track. But not sure where you can reach 0-75 on level track for a 465/9.
Greenhithe towards Dartford allows for 70mph, for the Gravesend-Victoria services, although /9s rarely run those. Northfleet-Gravesend is 70mph too but I believe that is a falling gradient.

Look on Ebay /Amazon for the gradient book. I paid £1.40.
@notadriver might be able to offer advice on where best to time 375s.465s.

On the subject of AC v DC.. Class 395s are severely limited by software so end up slower than a 375.
Class 450 much slower than Class 350/360 AC versions.
Class 700 much slower on DC v AC.

Where there is no level track we would try to average out the best runs on similar uphill/downhill gradients.
So if you recorded a 45 sec downhill and 50 sec uphill time then the average would be 47.5 secs.

 

[Deepgreen]

But 357 4 car is only 1600 hp and 357 4 car is like 2000 hp

?? They are the same units.

 

[SolomonSouth]

?? They are the same units.

Sorry I meant 377 4 car is 1600 hp

 

[ScottGallagher]

I had the misfortune to go on the line from Fenchurch st to Rainham yesterday and it was sluggish to say the least , it felt like we didn't even exceed 40 odd mph. In fact (but slightly going off topic) when youre one of the few passengers around you realise how grubby the whole thing is in both stations and stock. Fenchurch St is awful for a terminus it's everything negative about Euston in a microcosm.

 

[SolomonSouth]

Look on Ebay /Amazon for the gradient book. I paid £1.40.
@notadriver might be able to offer advice on where best to time 375s.465s.

On the subject of AC v DC.. Class 395s are severely limited by software so end up slower than a 375.
Class 450 much slower than Class 350/360 AC versions.
Class 700 much slower on DC v AC.

Where there is no level track we would try to average out the best runs on similar uphill/downhill gradients.
So if you recorded a 45 sec downhill and 50 sec uphill time then the average would be 47.5 secs.

Yeah I recorded a 700 at 73 secs to 60 on DC vs 40 secs to 53mph on AC. 53mph came in roughly 60 secs on DC, so equates to roughly 50 secs to 60 on AC.

 

[Dstock7080]

Obviously no comparison, S7 Stock in CBTC 0-40mph 23.48sec.

Let’s see a 357 and S7 compete away from Barking once SMA 6 commissioned next February!

 

[SolomonSouth]

Obviously no comparison, S7 Stock in CBTC 0-40mph 23.48sec.

Let’s see a 357 and S7 compete away from Barking once SMA 6 commissioned next February!

Lol man, 23.48 sec 0-40 for S7 stock? I might have to time one to 60, that is the quickest underground stock to 40 but I think a 357 is quicker to 40 still.
For a DC unit thats the fastest. 465/9 at about 25 seconds to 40 in a close second.

 

[Railperf]

Lol man, 23.48 sec 0-40 for S7 stock? I might have to time one to 60, that is the quickest underground stock to 40 but I think a 357 is quicker to 40 still.
For a DC unit thats the fastest. 465/9 at about 25 seconds to 40 in a close second.

Not sure there is anywhere you can time an S7 to 60mph. The only sections of track allowing 60mph are on the Metropolitan Line north of Finchley Road. Are S7 and S8 power to weight ratio s the same? I have seen 62mph on an S8 - so you can try 0-60mph - but it isn't quick - believe me! I reckon Jubilee line trains are faster - especially in the tunnels! Possibly the Victoria too, but no way of independently recording the speed as it is totally underground.
There are level starts on the Metropolitan line from Pinner Southbound and Northwood Northbound - but i don't think CBTC isn't available on the open air sections yet.

 

[SolomonSouth]

Not sure there is anywhere you can time an S7 to 60mph. The only sections of track allowing 60mph are on the Metropolitan Line north of Finchley Road. Are S7 and S8 power to weight ratio s the same? I have seen 62mph on an S8 - so you can try 0-60mph - but it isn't quick - believe me! I reckon Jubilee line trains are faster - especially in the tunnels! Possibly the Victoria too, but no way of independently recording the speed as it is totally underground.
There are level starts on the Metropolitan line from Pinner Southbound and Northwood Northbound - but i don't think CBTC isn't available on the open air sections yet.

The top speed of the 2009 stock on the Victoria line is 50mph.