Wheel slide protection (WSP)

[Kipperthecat]

Does wheel SLIDE protection only intervene under braking or will it intervene (wheel SLIP protection?) when accelerating ?

Will the system always apply sand ?

Will the system operate at lower speeds ?

Can WSP be supplemented by any manual sand application ?

Does the flow rate of sand remain constant or does it change, for example, when in certain steps or when braking / accelerating ?

 

[transportphoto]

This is a system that may vary between traction. Have you any specifics in mind that you’d like to know about?

 

[Kipperthecat]

This is a system that may vary between traction. Have you any specifics in mind that you’d like to know about?

Yes. Class 195’s v 156/150’s

 

[hexagon789]

Yes. Class 195’s v 156/150’s

195s have full WSP.

Originally 150/156 only had a basic system for acceleration, cutting power if a slip was detected then reapplying it to the same setting; I believe the 19x are more sophisticated and change gears to reduce tractive effort rapidly or something like that.

The 150/156 also had no WSP under braking as built, GA were the first to have their 156s fitted and ScotRail ones have it too now. Not sure about other 156s or 150s.

 

[skyhigh]

The 150/156 also had no WSP under braking as built, GA were the first to have their 156s fitted and ScotRail ones have it too now. Not sure about other 156s or 150s.

All Northern 150/156s are now fitted.

 

[hexagon789]

All Northern 150/156s are now fitted.

Perhaps all the tread-braked 15x have it for braking now then?

 

[skyhigh]

Perhaps all the tread-braked 15x have it for braking now then?

155s don't, I can't speak for other TOCs. I honestly can't remember if the 150/0s were fitted when they arrived from GWR or were done before they entered service.

 

[hexagon789]

155s don't, I can't speak for other TOCs. I honestly can't remember if the 150/0s were fitted when they arrived from GWR or were done before they entered service.

I suppose 155s being a small fleet the cost was perhaps not deemed worthwhile.

 

[Kipperthecat]

195s have full WSP.

Originally 150/156 only had a basic system for acceleration, cutting power if a slip was detected then reapplying it to the same setting; I believe the 19x are more sophisticated and change gears to reduce tractive effort rapidly or something like that.

The 150/156 also had no WSP under braking as built, GA were the first to have their 156s fitted and ScotRail ones have it too now. Not sure about other 156s or 150s.

Great.

So with regard my original post how does a 195 respond

 

[skyhigh]

I suppose 155s being a small fleet the cost was perhaps not deemed worthwhile.

They were in the plan to be done, I suspect they will be soon. The benefits in terms of increased life in wheelsets more than outweighed the cost of installation over the course of their remaining service life.

 

[dk1]

Since getting the excellent 745/755 we’ve basically forgotten all about WSP here in East Anglia.