Northern rolling stock changes post electrification

[northwichcat]

Is this so the Airport-Scotland services become 100% electric?

Yes

(Apparently you can't post a message with just Yes as the reply because it's too short!)

 

[DJL]

imo acceleration of 319s is poor compared to other units that operate on my lines (465s, 375s, 377s etc). But then you'd expect that since all those other units are younger than 319s.

No idea what they are like once they get onto OHLE though.

 

[W230]

No idea what they are like once they get onto OHLE though.

Just as s***!

 

[AM9]

Just as s***!

So are 319s able to draw power from the BML 660/750 DC supply to equal that taken from the MML 25kV supply?

 

[Class377/5]

Apparently Porterbrook did computer simulations to show how they would fair in comparison to other EMUs and the results they got weren't good on stopping services which is why they came up with an option for faster acceleration.

I've not seen anything that actually states the 319s acceleration means they can't be used on this line. As for not suitable for metro work, they've been doing that since they were built.

They do accelerate better on AC than DC tho.

 

[contrex]

So are 319s able to draw power from the BML 660/750 DC supply to equal that taken from the MML 25kV supply?

As far as I know the rating per unit is 990 kW (1327 hp) on either system.

 

[edwin_m]

Possibly the acceleration at higher speeds is more on AC because the AC system can deliver more power. Low speed acceleration is always going to be worse on 319s than 323s, simply a matter of having 1/4 of axles powered compared with 2/3.

 

[northwichcat]

I've not seen anything that actually states the 319s acceleration means they can't be used on this line. As for not suitable for metro work, they've been doing that since they were built.

They do accelerate better on AC than DC tho.

I agree that I've not heard issues about using 319s on Airport-Piccadilly services. The concern is more on services via Stockport and Guide Bridge.

Services stopping at Heaton Chapel and Levenshulme do cause massive problems if they are timed for a 323 and not operated as such. The xx:38 Piccadilly-Alderley Edge runs the bare minimum amount of time ahead of the xx:52 Liverpool-Norwich between Slade Lane Junction and Heaton Norris Junction.

Another example further down the WCML is the 17:09 Deansgate-Stoke can't be more than 2.5 minutes behind schedule between Macclesfield and Stoke or 17:35 Piccadilly-London service catches it up.

 

[contrex]

Possibly the acceleration at higher speeds is more on AC because the AC system can deliver more power. Low speed acceleration is always going to be worse on 319s than 323s, simply a matter of having 1/4 of axles powered compared with 2/3.

Also 319s are geared for 100 mph outer suburban work. Porterbrook have discussed re-gearing for 75 mph max speed, which would improve the acceleration, and/or replacing the traction package.

 

[DJH1971]

Also 319s are geared for 100 mph outer suburban work. Porterbrook have discussed re-gearing for 75 mph max speed, which would improve the acceleration, and/or replacing the traction package.

Thought their max speed was 90mph?

 

[Class 170101]

319s is 100mph top speed and is used on MML Fast Lines.

 

[northwichcat]

319s is 100mph top speed and is used on MML Fast Lines.

Indeed. However, 100mph class 170s have also been used on the MML and people comment about those having poor acceleration and struggling with all-stops services.

Sometimes fast and slow are just names. The Northern Rail Manchester-Chester (142/150/156) service used to depart Piccadilly at xx:24, the same time a XC Voyager for Birmingham and beyond did. The Northern service got put on the fast line and the XC on the slow due to the Northern service needing to cross the northbound line on departure from Stockport, even though the XC service had departed platform 1 at Stockport before the Northern service had arrived at platform 2.

 

[Class 170101]

I think in the case of the MML it does apply. Maximum speed on the Fast Lines now upto 125mph, 100mph on slow lines maximum and probably somewhat lower. Even prior to the upgrade 110mph was available on the Fast Lines.

 

[AM9]

Possibly the acceleration at higher speeds is more on AC because the AC system can deliver more power. Low speed acceleration is always going to be worse on 319s than 323s, simply a matter of having 1/4 of axles powered compared with 2/3.

Probably more to do with 323s having power to weight figure of 13 hp/tonne compared with the 319s 9.48 hp/tonne. Low/medium speed acceleration will also be helped by 75mph gearing vs 100mph.

 

[Geeves]

Just a small thing AM9, 323s are 90mph units though Im sure they would easily do 100 if they were allowed!

 

[DJH1971]

Just a small thing AM9, 323s are 90mph units though Im sure they would easily do 100 if they were allowed!

Thought they could only do 75mph?

 

[edwin_m]

Probably more to do with 323s having power to weight figure of 13 hp/tonne compared with the 319s 9.48 hp/tonne. Low/medium speed acceleration will also be helped by 75mph gearing vs 100mph.

However much power is available, the maximum acceleration at low speeds is always going to be limited by the proportion of weight on motored axles and by the available adhesion. I do agree power and gearing will come into play at higher speeds.

 

[AM9]

However much power is available, the maximum acceleration at low speeds is always going to be limited by the proportion of weight on motored axles and by the available adhesion. I do agree power and gearing will come into play at higher speeds.

That's why I said low/medium speeds. At what speed would full motor power be available without wheelslip on normal rail conditions?

 

[Class377/5]

I agree that I've not heard issues about using 319s on Airport-Piccadilly services. The concern is more on services via Stockport and Guide Bridge.

Services stopping at Heaton Chapel and Levenshulme do cause massive problems if they are timed for a 323 and not operated as such. The xx:38 Piccadilly-Alderley Edge runs the bare minimum amount of time ahead of the xx:52 Liverpool-Norwich between Slade Lane Junction and Heaton Norris Junction.

Another example further down the WCML is the 17:09 Deansgate-Stoke can't be more than 2.5 minutes behind schedule between Macclesfield and Stoke or 17:35 Piccadilly-London service catches it up.

Have to admit I'm not very familiar with the Stockport route if I'm honest so my comments were over the Airport services.

Just a small thing AM9, 323s are 90mph units though Im sure they would easily do 100 if they were allowed!

The 319s can do over 110mph. Just not rated for it.

 

[AM9]

The 319s can do over 110mph. Just not rated for it.

So does that mean that their motors' balancing speeds have been set too high with the gearing. If so, then operational performance has been thrown away for over 25 years!

 

[Class377/5]

So does that mean that their motors' balancing speeds have been set too high with the gearing. If so, then operational performance has been thrown away for over 25 years!

Nothing to do with that. All units are capable of 10% over speed beyond there rated speed. Note other more modern 100mph units are capable of far higher speeds.

When Bombardier did 110mph testing on a 379 it simply rewrote the software to allow high speeds (meaning the 379 needed to be capable of reaching 121mph) as the motors were capable of more despite the fact the 379 are '100mph' units.

 

[childwallblues]

Also 319s are geared for 100 mph outer suburban work. Porterbrook have discussed re-gearing for 75 mph max speed, which would improve the acceleration, and/or replacing the traction package.

As Chat Moss is now a 90 mph railway except around Astley what is the point of having a 75 mph maximum speed?
Also reducing the units to three car would on some services reduce capacity as quite a number of services are already booked for 2 x 2 car units.

 

[fowler9]

However much power is available, the maximum acceleration at low speeds is always going to be limited by the proportion of weight on motored axles and by the available adhesion. I do agree power and gearing will come into play at higher speeds.

As Chat Moss is now a 90 mph railway except around Astley what is the point of having a 75 mph maximum speed?
Also reducing the units to three car would on some services reduce capacity as quite a number of services are already booked for 2 x 2 car units.

Just because it is 90 mph capable doesn't mean the most efficient way to use it is for every train to reach 90 mph.

 

[Darren R]

....Also reducing the units to three car would on some services reduce capacity as quite a number of services are already booked for 2 x 2 car units.

If the 319s were to be converted to three car (and I was under the impression that three car EMU operation on the Lancashire Triangle was the preferred option) then peak services could be doubled up. Eight car trains would be overkill, and require a fairly extensive programme of platform lengthening, whereas the latter wouldn't be quite the same problem for six car trains.

 

[LNW-GW Joint]

As far as we know, nothing is going to happen to the initial 14x319s for Northern introduction.
Reconfiguring/upgrades/retractioning is for the future franchise.
They have a couple of years to try them out and decide any changes.
Next year they will be running in DMU times anyway, because there won't be enough to fully convert any one service.

 

[WatcherZero]

Hitachi are building a three car demonstrator to come to the UK next year and be lent out to TOC's for evaluation. I think the length is highly suggestive of geographically where they are targeting for potential orders, if they had been targeting orders for Southern tocs it would probably have been a 4 car unit.

 

[edwin_m]

Hitachi are building a three car demonstrator to come to the UK next year and be lent out to TOC's for evaluation. I think the length is highly suggestive of geographically where they are targeting for potential orders, if they had been targeting orders for Southern tocs it would probably have been a 4 car unit.

It could also be that three cars is the minimum configuration for "modular" EMU designs - 2-car would need special engineering to put the transformer/pantograph in a cab car. It would also create problems with closely-spaced pantographs when running in multiple, admittedly not an issue if you only build one! Given that they can show all the key features in a 3-car there's no real need to build extra cars for a demonstrator.

What is much more interesting in relation to the target market is whether they build 23m or 20m (or some other length) and whether they include third rail compatibility. 23m would be out of gauge on many Southern routes and strongly suggest they are aiming north of London. However for a demonstrator, if I had any money it would be on a "universal" 20m dual-voltage with the brochure saying it is available in other configurations.

 

[northwichcat]

Next year they will be running in DMU times anyway, because there won't be enough to fully convert any one service.

I thought two diagrams are supposed to switch, so those two diagrams could be timed as EMU running. (TPE time some Scottish services for class 185s but most are timed for 350s.) I imagine the issue is the chance of needing to use a DMU to fill in for a 319 will be very high with such a small fleet.

 

[Fincra5]

I pass on FCC's a fair bit... I don't think 319s acceleration is that poor. In the real world anyway and not just on paper... The brakes do seem to be v.good on 319s (unless is wet )

 

[northwichcat]

I pass on FCC's a fair bit... I don't think 319s acceleration is that poor. In the real world anyway and not just on paper... The brakes do seem to be v.good on 319s (unless is wet )

The question isn't whether it's poor, it's whether they have lightning quick acceleration like the 323s and if not what impact would running 319s on a service timed to run as a 323 may have.

So they have problems when it's wet :eek: