Maxmium possible speed a unit can do

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221101 Voyager

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Hi I was wondering, with train motors they have a maxmium speed, but I've heard it is possible that they can go faster.

For example, 350s do 110mph, but I've heard the motors are capable of higher speeds if they keep the throttle open long enough and remove any speed limiters.

What's the maximum possible speed a

313 can do
321 can do
350 can do
390 can do

Thanks. :D
 
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centro-323

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Not sure about those units, but one of the 80x family ended up doing over 145mph this year. Apparently the driver thought they'd set the speed limiter to 125, but they forgot to confirm the setting. They set the power controller to maximum and didn't realise the speed until they looked down again a while later.

Oops.
 

221101 Voyager

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Not sure about those units, but one of the 80x family ended up doing over 145mph this year. Apparently the driver thought they'd set the speed limiter to 125, but they forgot to confirm the setting. They set the power controller to maximum and didn't realise the speed until they looked down again a while later.

Oops.
Oh dear! Bet the driver got in some serious trouble for that!

He or she was obviously rushing back to the depot to get their McDonald's for dinner! ;)
 

hexagon789

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Hi I was wondering, with train motors they have a maxmium speed, but I've heard it is possible that they can go faster.

For example, 350s do 110mph, but I've heard the motors are capable of higher speeds if they keep the throttle open long enough and remove any speed limiters.

What's the maximum possible speed a

313 can do
321 can do
350 can do
390 can do

Thanks. :D
They should all be tested to a 10% overspeed above normal service speed generally.

The 390 afaik has only been to 145mph though not 154, unless I've missed something.

But a 321 should have been to 110mph.

A 317 has been to 108mph, not sure about any faster.

A 313 is older, so might not have not tested to a 10% overspeed as standard, but they can certainly manage 80mph.

A 110mph 350 should have been to at least 121 mph during 110mph certification testing.
 

221101 Voyager

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They should all be tested to a 10% overspeed above normal service speed generally.

The 390 afaik has only been to 145mph though not 154, unless I've missed something.

But a 321 should have been to 110mph.

A 317 has been to 108mph, not sure about any faster.

A 313 is older, so might not have not tested to a 10% overspeed as standard, but they can certainly manage 80mph.

A 110mph 350 should have been to at least 121 mph during 110mph certification testing.
Ah right, thanks for that information! :D
 

robbeech

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I’ve no doubt several 156s and 153s have done 90mph coupled to a leading 158 etc.
 

swt_passenger

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Hi I was wondering, with train motors they have a maxmium speed, but I've heard it is possible that they can go faster.

For example, 350s do 110mph, but I've heard the motors are capable of higher speeds if they keep the throttle open long enough and remove any speed limiters.

What's the maximum possible speed a

313 can do
321 can do
350 can do
390 can do

Thanks. :D
Throttle isn’t really a term used with electric traction…
 

swt_passenger

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True, is the word notch more suitable for Electrics then?
Don’t think so, a “notch“ is just a position of something. I think the various levers have different names in different electric stock, depends if combined with the brakes. I’m sure someone will know a better generic term…
 

221101 Voyager

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Don’t think so, a “notch“ is just a position of something. I think the various levers have different names in different electric stock, depends if combined with the brakes. I’m sure someone will know a better generic term…
For trains with a combined throttle and brake lever we can call the PBC (Power brake controller).

Trains with a seperate throttle can be called notches.

Is that better? :D
 

221101 Voyager

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McDonald's???!!!
We dine only on the finest Swan, and Chateaubriand i'll have you know! ;)
Of course you do! That's assuming your 180 makes it there without breaking down of course! ;)

Just out of interest, is that why your user name is Kneedown? As you spent a lot of time on your knees trying to fix 180s and praying they don't go wrong again after you've sorted the fault? ;)

Also, what's the maximum possible speed of a 180, when it runs of course?
 

O L Leigh

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A 317 has been to 108mph, not sure about any faster.

I once had to take a pair empty to Cambridge due to a failure and was challenged by a colleague to see if I could beat the supposed record of 113mph through Shelford. Presumably this would have been set in the pre-OTMR days.

I declined.
 

Domh245

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For trains with a combined throttle and brake lever we can call the PBC (Power brake controller).

Trains with a seperate throttle can be called notches.

Is that better? :D

Notch falls down when you get to camshaft units (which do have notches on their power controller, but these don't directly control what power the motors are getting - only how far/fast the camshaft goes through it's resistances/field changes/etc), or Tap changers.

I'd have personally gone with a nice vague "if they leave it on full power long enough"!

The original question about "what's the fastest it can go" is ultimately going to depend on a variety of factors. The maximum speed that any train could go is the speed where the propulsive force from the traction motors is balanced out by the resistive forces (rolling resistance, drag, working against gravity on a gradient) - something that realistically can only be done by testing a given train, and dependant on where and when the test is done!
 

CBlue

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I've heard stories of drivers nudging 110 with Class 365's on the ECML although from how it sounded it was an accidental overspeed rather than deliberate.
 

hexagon789

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I once had to take a pair empty to Cambridge due to a failure and was challenged by a colleague to see if I could beat the supposed record of 113mph through Shelford. Presumably this would have been set in the pre-OTMR days.

I declined.
Oh I would loved to see a 317 scream along at 113+, that would have been something.

I do have sources for the different speeds, and if I find a credible higher one I cross out the lower speed and update my records.

I've heard stories of drivers nudging 110 with Class 365's on the ECML although from how it sounded it was an accidental overspeed rather than deliberate.
It should be possible, they have at a rough calculation, enough power to manage about 115 or so at least, most of the late-1980s/early 1990s units do. Obviously load, line voltage, gradients etc are all going to affect things.

A 159 was officially allowed 99mph when new as part of a record run to Salisbury, 99 was touched 3 times on the run and supposedly 99 was the maximum the manufacturer would allow without voiding the warranty.

However, the Class 158 record run on the Edinburgh and Glasgow touched 109mph and they are very similar trains, so presumably BR decided the warranty didn't matter for the 158s?

I’ve no doubt several 156s and 153s have done 90mph coupled to a leading 158 etc.
Try more like 100! ;)

Of course you do! That's assuming your 180 makes it there without breaking down of course! ;)

Just out of interest, is that why your user name is Kneedown? As you spent a lot of time on your knees trying to fix 180s and praying they don't go wrong again after you've sorted the fault? ;)

Also, what's the maximum possible speed of a 180, when it runs of course?
The highest I have for a 180 is 138mph which is just about the overspeed margin (137.5).

Notch falls down when you get to camshaft units (which do have notches on their power controller, but these don't directly control what power the motors are getting - only how far/fast the camshaft goes through it's resistances/field changes/etc), or Tap changers.

I'd have personally gone with a nice vague "if they leave it on full power long enough"!

The original question about "what's the fastest it can go" is ultimately going to depend on a variety of factors. The maximum speed that any train could go is the speed where the propulsive force from the traction motors is balanced out by the resistive forces (rolling resistance, drag, working against gravity on a gradient) - something that realistically can only be done by testing a given train, and dependant on where and when the test is done!
With really old resistance control you could do something with the resistances I think called "shunting" when in weak field bit it was frowned on iirc? I'm taking about really old units without automatic notching camshafts where resistance control was manual. It did something further to reduce the back EMF and gave a further speed boost. Probably using the wrong terms.

Anyway, an American GG1 electric, these were designed for 100mph but the Pennsylvania was an 80mph road, made at least 115mph on more than one occasion through this expedient method of obtaining a higher speed.

A 153 did 100mph coupled to a 170 once.

The engine didn't exactly survive, but you know....
Doesn't surprise me
 
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221101 Voyager

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I've heard stories of drivers nudging 110 with Class 365's on the ECML although from how it sounded it was an accidental overspeed rather than deliberate.
Wow! That must be cool to have been on that. 8-)

Oh I would loved to see a 317 scream along at 113+, that would have been something.

I do have sources for the different speeds, and if I find a credible higher one I cross out the lower speed and update my records.


It should be possible, they have at a rough calculation, enough power to manage about 115 or so at least, most of the late-1980s/early 1990s units do. Obviously load, line voltage, gradients etc are all going to affect things.

A 159 was officially allowed 99mph when new as part of a record run to Salisbury, 99 was touched 3 times on the run and supposedly 99 was the maximum the manufacturer would allow without voiding the warranty.

However, the Class 158 record run on the Edinburgh and Glasgow touched 109mph and they are very similar trains, so presumably BR decided the warranty didn't matter for the 158s?

The highest I have for a 180 is 138mph which is just about the overspeed margin (137.5).
That’s some seriously impressive stuff! :D

How about a 220/221/222? Did they get up to as much as the 180?
 

Ken H

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2 things here. The speedos are driven from the wheels (Or they were). So the amount of wear on the wheels, i.e their actual radius, affects the speed shown on the speedo. So look at the 4 speedos on 2 couples units at the same time and you will see different speeds.

For electric trains, if you overspeed the centrifugal force of the armature of the motor will be too great, so there is a danger of it bursting. How much overspeed is necessary to cause such a failure, I dont know. I assume that is in the train spec, and is proven by the manufacturer. I dont want to be on a train when a motor bursts to find out!
 

CW2

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The design speed of the 390s was 140mph, and I believe 10% overspeed testing to 154mph took place overnight on the Trent Valley north of Nuneaton, under possession. I have an idea Roger Ford was invited aboard one of the test runs and subsequently wrote up the details in Modern Railways.
 

hexagon789

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2 things here. The speedos are driven from the wheels (Or they were). So the amount of wear on the wheels, i.e their actual radius, affects the speed shown on the speedo. So look at the 4 speedos on 2 couples units at the same time and you will see different speeds.

For electric trains, if you overspeed the centrifugal force of the armature of the motor will be too great, so there is a danger of it bursting. How much overspeed is necessary to cause such a failure, I dont know. I assume that is in the train spec, and is proven by the manufacturer. I dont want to be on a train when a motor bursts to find out!
Deltics were prone to this if driven too much over their motor gearing rating of 106mph, in later life after the HSTs came in and it was known they would be thrashed to death on the semi-fasts the motors were beefed up with the armature casings impregnated with a resin and baked in. This the highest recorded speeds for Deltics are concentrated more towards the end of their lives on BR than the early years. You also had the ECML fettled up for 125mph by that point as well, which gave drivers extra incentive to run hard it seems.

The design speed of the 390s was 140mph, and I believe 10% overspeed testing to 154mph took place overnight on the Trent Valley north of Nuneaton, under possession. I have an idea Roger Ford was invited aboard one of the test runs and subsequently wrote up the details in Modern Railways.
I expected that but couldn't find a source, so went with the oft-quoted 145 figure.
 

Snow1964

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They should all be tested to a 10% overspeed above normal service speed generally.

The 390 afaik has only been to 145mph though not 154, unless I've missed something.

But a 321 should have been to 110mph.

A 317 has been to 108mph, not sure about any faster.

A 313 is older, so might not have not tested to a 10% overspeed as standard, but they can certainly manage 80mph.

A 110mph 350 should have been to at least 121 mph during 110mph certification testing.

Should be pointed out that most certifications are with new units with wheels maximum size, if they have been turned a few times the circumference could be 0-4% smaller, so max speed will be accordingly reduced.
 

37057

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2 things here. The speedos are driven from the wheels (Or they were). So the amount of wear on the wheels, i.e their actual radius, affects the speed shown on the speedo. So look at the 4 speedos on 2 couples units at the same time and you will see different speeds.

Unless they're set up accordingly after tyre turning / new wheelsets.
 

Tynwald

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All train speed systems have wheel wear compensators. Speedos have to be deadly accurate. the system is also used for the WSP control.
I have travelled 112mph in a 319, down Stoke bank.
 
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