The Anonymous Widower

Class 399 Tram-Trains In Service

On my two day trip to Sheffield, I reckon that I saw six of the seven Class 399 tram-trains in service on the Supertram.

These pictures were taken on a quiet Saturday morning trip from the station to Herdings Park.

Current Service

Currently, the Class 399 tram-trams are running on the Purple Route from Cathedral to Herdings Park, which is generally tun at a frequency of  two trams per hour.

If you arrive in Sheffield station and don’t feel like walking up the hill, you take any of the trams from the  stop on the station side of the tracks.

But take a tram going to Cathedral and over the two and a bit days I was in Sheffield, it was always a Class 399 tram-train.

Comparison With Current Fleet

The Class 399 tram-trains and the existing Siemend-Duewag Supertram are surprisingly similar in several ways.

• Both have three sections and four doors on either side.
• The Siemens tram is 34.8 metres long, whereas the Class 399 is 37.2 metres long.
• The Siemens tram weights 46.5 tonnes, whereas the Class 399 is a lot heavier at 66.1 tonnes.
• The Siemens tram has installed power of 1108 kW, whereas the Class 399 has just 870 kW.
• The Siemens tram has room for 86 sitting and 155 standing passengers, whereas the Class 399 has room for 88 and 150 respectively.
• The seats and their arrangement are vaguely similar.
• Neither tram has wi-fi.

The big  difference other than the tram-train capability and what that entails, is that the Class 399 tram-train is faster with a 100 kph top speed, as against the 80 kph of the Siemens tram.

Other differences are detailed in the next sub-sections.

Step-Free Access

Getting on and off both trams is step-free and I saw people in wheel-chairs on both vehicles. One was easily pushed into a Class 399.

These pictures show the steps inside the two trams.

There is only a single-step on the Class 399 tram-train, whereas the Siemens tram has more.

Neither tram is a hundred percent step-free.

Weight

Note that the weight of the Class 399 tram-train is more than that of the Siemens tram.

As the two vehicles are of a similar size, could this mean that any of the following causes the weight increase.

• The electrical equipment needed to handle 15/25 KVAC power.
• The weight of the two extra traction motors.
• Strengthening for main line operation.

As someone, who has ridden for a few hours in both the Karlsruhe and Sheffield variants of the Citylink tram-train, they certainly don’t ride badly.

Performance

The current Siemens tram has 1108 kW of power and a weight of 46.5 tonnes, which gives an installed power/weight ratio of 23.8 kW/tonne.

The Class 399 tram-train has 870 kW of power and a weight of 66.1 tonnes, which gives an installed power/weight ratio of 13.1 kW/tonne.

So it would appear that the Class 399 tram-trains may not have the acceleration and hill-climbing capability of the Siemens trams.

However look at this data sheet on the Stadler Rail Espana web site for the Class 399 tram-train.

It clearly shows that the tram has four bogies and the text says that three are motored and one is a trailer. So this means that the central car is not a trailer and that power must be distributed along the tram, which probably puts the power to the rail in a more efficient way.

I did speak to a driver and he told me that on some of the hills the Siemens trams will strruggle with a full load, but the Class 399s can go up the hills at 40 mph.

The Class 399 tram-trains are very similar to the Stadler tram-trains in Karlsruhe, where the hills are much stiffer than Sheffield.

So it would appear that the layout of six smaller motors in a more modern vehicle probably does the trick.

Energy Efficiency

The question has to be asked if, as the Class 399 tram-trains have twenty-one percent less installed power, does this result in a saving of electricity use?

Comparison With Karlsruhe’s Tram-Trains

The Karlsruhe and Sheffield tram-trains are both variants of the Vossloh Citylink tram-train, that is now built by Stadler at Valencia in Spain.

The tram-trains in Karlruhe would appear to be very similar to the Class 399 tram-train, with a few small technical differences.

• They work on 750 VDC and 15 KVAC overhead wires, whereas the Class 399 can work on 750 VDC and 25 KVAC.
• As an electrical engineer, I wonder if the electrical systems are the same in both tram-trains and both can work 750 VDC and 15-25 KVAC, so they could work cross-border routes between say Germany and France.
• They have couplers to work in multiple.
• They have different passenger door arrangements.
• The driver’s cab windows have different arrangement.

These pictures show Karlsruhe’s tram-trains.

Imagine these trams in Supertram colours on the streets of Sheffield.

Take a close look at picture 4.

You will notice that the Karlsruhe tram-trains have an obvious coupling and it can be assumed that they can work in ,multiple, although I don’t seem to have seen it happening.

Picture 4, also shows passengers apparently sitting in the back cab of the tram-train.

The fifth picture was taken from sitting inside the tram-train looking backwards, over the folded-down driver’s desk.

This feature wasn’t being used in Sheffield and this could be for one the following reasons.

• The Class 399 tram-trains don’t have the feature installed.
• There has been a Health and Safety decision.
• It takes perhaps ten minutes to fold up the driver’s desk and this would slow the timetable.

It’s a pity , as this feature of German trams is very common and popular.

Comparison With Class 144 Train

The Class 399 tram-trains and Northern’s Class 144 train will share routes and on some routes the tram-trains may even take over from the Pacers.

So how do the two trains compare?

• The Class 399 has room for 88 sitting and 150 standing passengers, whereas the Pacer has 99 seats in a two-car and 157 in a three-car train.
• The Class 399 weighs 66.1 tonnes, whereas a two-car Pacer weighs 49.2 tonnes and a three-car weighs 72 .7 tonnes.
• The Pacer has a toilet.
• The Class 399 is air-conditioned, whereas the Pacer relioes on waste heat from the engine.
• The Pacer is a 75 mph train, but seems to operate most of the time at 60 mph
• The Class 399 has installed power of 870 kW, whereas the Pacer has just 336 kW.
• The Pacer is thirty-year-old crap, that should have been strangled at birth, whereas the Clas 399 is a modern unit.

You could argue, that I’m being biased, as the tram-train can’t operate without electrification.

But it can!

Chemnitz or Karl Marz Stadt as the East Germans renamed it. also runs Stadler Citylink tram-trains, which are similar to the Class 399 tram-trains.

But the tram-trains in Chemnitz are different in that instead of being dual-voltage like Sheffield and Karlsruhe, they have a diesel-generator to power them away from the 750 VDC overhead wires.

This data sheet gives a few details of the Chemnitz Hybrid tram-train. The data sheet doesn’t specify the power of the diesel powerpack, but the much heavier Class 769 train uses two rail-proven MAN diesel engines of 390 kW each.

In this article on Rail News, which is entitled Penistone Line Is Chosen For £24m Tram Trains Trial, the original trial is described and this is said.

One of the biggest initial tasks is to set a specification for the building of the five diesel-electro hybrid tram trains at a cost of £9 million.

The article was written in 2008 and hybrid Citylink tram-trains didn’t run in Chemnitz until 2016.

So the original proposal envisaged using hydrid diesel tram-trains.

Why not use them in Sheffield?

Operational Details

The Class 399 tram-trains have other features that became apparent on my observations.

Battery Use

Passing a Class 399 tram-train, I took this picture.

I hadn’t thought about it before, but batteries on a tram must have similar uses to those in any vehicle.

• Starting up the vehicle.
• Raising the pantograph, on an electric tram, train or locomotive.
• Opening the powered doors.
• Providing lighting and other important services in a power failure.
• Being able to move the vehicle a short distance in case of a complete overhead power failure.
• With a dual-voltage vehicle, it must be there in case the changeover isn’t successful.

But with a tram-train, battery operation surely opens up the possibility of changing between the tram and heavy rail lines using very simple track without electrification, points and cross-overs.

The driver would do the following.

• Pan down on one network.
• Use battery power to move perhaps fifty or a hundred metres to the other system.
• Raise the pantograph on the other network.

Provided the driver obeys the rules and the signals, it should be a safe transfer.

Regenerative Braking

This article on the Railway Gazette is entitled Karlsruhe orders Vossloh tram-trains.

These tram-trains were the first of the Citylink family of tram-trains, of which the Class 399 tram-trains are a member.

This is said.

The three-section steel-bodied tram-trains will incorporate extensive crashworthiness design elements and provision for regenerative braking. Top speed will be 80 km/h, with the four bogies having pneumatic secondary suspension. The air-conditioned interior will have 104 seats cantilevered from the sides for easy cleaning.

How do the Citylink tram-trains handle the regenerative braking?

Two methods are possible.

• They return the braking energy to the overhead wires.
• They store it in their battery for reuse.

In the Wikipedia entry for the Supertram, there is a section called Overhead Wiring. This is said.

The contact wires are twin cadmium copper ones, twin wires being necessary because of the high installed power rating of the trams (1 megawatt). The regenerative braking on the tram feeds current back into the wires.

So any braking energy can be returned to the wires.

But as the Railway Gazette article dates from 2011, I wonder if the trams have been developed to use battery storage?

How Far Could The Tram-Train Go On Battery Power?

I’ll assume the following.

• A New Routemaster bus battery of 75 kWh can be fitted to the Class 399.
• Running on an easy track, the Class 399 could need  5 kWh for each car-mile.

This would give a range of five miles.

Note.

1. The stiffer the route the smaller the range.
2. Battery capacity should increase through the years.
3. Battery cost should decrease through the years.
4. Charging stations can be fitted at station stops.

The only certainties are that practical battery range will increase and battery cost will decrease.

Conclusions

These tram-trains have been well worth waiting for.

If I was in charge of the Sheffield Supertram and a decision was made to replace the original Siemens trams, I would think seriously about going to Stadler for a replacement fleet.

If the fleet was all Class 399 tram-trains, this could offer other savings.

• The lower-power of the Class 399 tram-trains might cut electricity use.
• Regenerative braking using onboard batteries saves electrification costs.
• Would expensive twin cadmium copper contact wires still be needed?
• One tram type would save costs in maintenance and staff training.

New must-have features like wi-fi and 4G boosters could be added, as the technology has now been developed, since the Siemens trams were built.

 

October 15, 2017 - Posted by AnonW | Transport/Travel | Citylink, Class 399 Tram-Train, Sheffield, Sheffield Supertram, Tram-Train