Class 700 jerky acceleration

[Crithylum]

I am currently in coach 12 of a class 700, and when it pulls away from stations the acceleration is very jerky in the intial acceleration. It feels like it is oscillating from full power to half power, taking roughly a second or two per cycle. Does anyone have any clue as to why this is happening?

 

[hexagon789]

I am currently in coach 12 of a class 700, and when it pulls away from stations the acceleration is very jerky in the intial acceleration. It feels like it is oscillating from full power to half power, taking roughly a second or two per cycle. Does anyone have any clue as to why this is happening?

Wheelslip?

 

[Ash Bridge]

Caused by poor railhead conditions due to the adverse weather perhaps?

 

[hexagon789]

Caused by poor railhead conditions due to the adverse weather perhaps?

That was my guess too.

We are into autumn now, in more ways than one

 

[Ash Bridge]

That was my guess too.

We are into autumn now, in more ways than one

Has certainly been a little bit wild down in these parts through this afternoon!

 

[hexagon789]

Has certainly been a little bit wild down in these parts through this afternoon!

Been wild all round mate!

Autumn is well and truly upon us!

 

[Crithylum]

It was raining, so that could be why. Although it felt very periodic and jerky, as if the wheelslip was on a very low refresh rate or very rudimentary. It was certain way jerkier than notching up different resistors on a 72/73 stock for example.

 

[frankmoh]

Wheelslip? I've noticed some rather concerning noises from the Southeastern Electrostars coming out of Waterloo East or Lewisham as of recent.

 

[Supercoss]

Are you able to advise what location and which direction you where travelling ?

 

[Crithylum]

Cambridge to Stevenage southbound. Happened every station pulling away except Cambridge where we pulled away slowly.

 

[Crithylum]

I had a journey on a 755 yesterday. There was audible wheelslip under acceleration, and despite that I couldn’t feel anything. It appears that Stadler has a far superior wheelslip management (and I do mean far superior)

 

[bahnause]

I had a journey on a 755 yesterday. There was audible wheelslip under acceleration, and despite that I couldn’t feel anything. It appears that Stadler has a far superior wheelslip management (and I do mean far superior)

'Superior' is always subjective. There are many ways in which a control system can be optimised. For example, to ensure smooth running, reduce wear or maximise transferable traction. Depending on the distribution of the drive axles, train length, type of coupling and whether the track conditions are constant or changing, the result will also vary. Some of our vehicles also enable the train driver to adjust the system. Depending on the difference between the amount of traction demanded by the driver and the amount of traction available, the control system works more or less 'aggressively'.

 

[whoosh]

I had a journey on a 755 yesterday. There was audible wheelslip under acceleration, and despite that I couldn’t feel anything. It appears that Stadler has a far superior wheelslip management (and I do mean far superior)

Maybe it was superior, maybe the railhead conditions in that location were just better.

Maybe, a class 700 has 4 motor cars in an 8 car train (or 6 in a 12 car), and will experience more jerking around as some axles have grip and others experience slip. There will be less jerking in a shorter train.