319s in leaf fall season

[northwichcat]

I've noticed that the Merseyrail 507s and 508s perform much poorer during leaf fall season than the newer EMUs in the North West (350s on Liverpool-Birmingham and 323s in the Manchester area.) Also the 150s and 156s don't perform as well as the 170s and 185s in leaf fall season. So I was wondering how the 319s would be expected to perform in leaf fall season when they move to the North West.

 

[edwin_m]

In acceleration or braking? Many of the factors that determine adhesion only affect one mode, such as the proportion of motored axles or the configuration of any sanding system.

 

[northwichcat]

In acceleration or braking? Many of the factors that determine adhesion only affect one mode, such as the proportion of motored axles or the configuration of any sanding system.

Either. If on average day it takes say 5 minutes 30 seconds between departing station A and arriving at station B, would on a bad autumnal day, a 319 perform better than other units or worse than other units?

 

[61653 HTAFC]

Can leaf-mulch affect the conductor rail in 3rd rail areas? If so, that might explain the difference between Merseyrail and the others.
Also, 323s have more powered wheels as they have 2 motor cars compared to just one in the 507/508s and the 319s (and indeed the 350s), so that might be a factor too.

 

[edwin_m]

Can leaf-mulch affect the conductor rail in 3rd rail areas? If so, that might explain the difference between Merseyrail and the others.
Also, 323s have more powered wheels as they have 2 motor cars compared to just one in the 507/508s and the 319s (and indeed the 350s), so that might be a factor too.

Don't the 507/508 units have motors on all axles in both end cars like the 323s, so both are two thirds of axles motored. 350s certainly have motors in each end car but I can't immediately turn up any info on whether this is one or both bogies. 319s definitely have only one power car with all axles motored.

The older DCs on the 319 and the 507/508 is probably slightly worse at dealing with slips than AC motors are. But 319s may be fitted with AC motors before they move north, as with the demonstrator refurbished 317 and planned for the 321.

As to braking, all these classes have disc brakes but the wheelslide protection on the newer units is probably more effective.

 

[507 001]

508s apparently have better WSP than 507s.

507s & 508s have both driving cars motored with 4 110bhp GEC motors in each.

350s also have both end cars motored.

 

[Silv1983]

I've noticed that the Merseyrail 507s and 508s perform much poorer during leaf fall season than the newer EMUs in the North West (350s on Liverpool-Birmingham and 323s in the Manchester area.) Also the 150s and 156s don't perform as well as the 170s and 185s in leaf fall season. So I was wondering how the 319s would be expected to perform in leaf fall season when they move to the North West.

Maybe starting away at stations - but not sure for braking. As you probably know the 150/156's have tread brakes which cleanse the tyre surface with a short application meaning 50% less gunk between surface areas -whereas the other 2 have disc brakes and suffer more from a build up of contamination. At least they used to - perhaps they're have something in place to scrub the debris off as they turn.

 

[tbtc]

I've noticed that the Merseyrail 507s and 508s perform much poorer during leaf fall season than the newer EMUs in the North West (350s on Liverpool-Birmingham and 323s in the Manchester area.)

I thought that 323s were pretty poor at dealing with leaves - the Cross City line in the West Midlands seems to be one of the worst affected each Autumn (?)

 

[northwichcat]

I thought that 323s were pretty poor at dealing with leaves - the Cross City line in the West Midlands seems to be one of the worst affected each Autumn (?)

I only said they performed better than the Merseyrail units. Last week the 507s and 508s on the Chester line were struggling more than the 142s through Delamere Forest and that is very difficult to do!

 

[BravoGolfMike]

Maybe starting away at stations - but not sure for braking. As you probably know the 150/156's have tread brakes which cleanse the tyre surface with a short application meaning 50% less gunk between surface areas -whereas the other 2 have disc brakes and suffer more from a build up of contamination. At least they used to - perhaps they're have something in place to scrub the debris off as they turn.

This is true, but 170/185 will have WSP and auto sanders which makes a massive difference.

 

[O L Leigh]

As a broadly similar comparison...

Cl315s can get the power down better in the autumn than Cl317s, to the extent that (in the past at least) a Cl317 could end up stalled on a gradient where a Cl315 would go up it. It's partly to do with having more driven axles but also due to being a bit lighter so that there is less weight to accelerate. Under braking they are about the same.

O L Leigh

 

[8J]

Ive noticed that the units with resistor based camshaft systems tend to slip under acceleration as they are more vigorous through the stages of motor application. Another thing that should be noted is that merseyrails Chester line runs through industrial areas and residue from the factories can cause issues on the tracks.

I still think that the 508's will perform better than the 319's though.