Siemens ER 20

Updated: August 2026 – A modern locomotive that looks like an electric at first glance – but has no pantograph and can be heard running on diesel while standing still: that’s the Siemens ER 20, better known as the Eurorunner. This page shows you how to recognise it, what the type name means and why it plays a special role among modern diesel locomotives.

What is the Siemens ER 20?

The ER 20 is a four-axle diesel-electric mainline locomotive from Siemens, built at the München-Allach locomotive plant. A diesel engine drives a generator, which in turn feeds the traction motors in the two bogies. Power output is around 2,000 kW, top speed 140 km/h.

This combination explains its special role: most modern diesel locomotives from private operators are tailored to freight and shunting work and designed for correspondingly lower speeds. The Eurorunner, by contrast, is fast enough to take on passenger duties on non-electrified lines as well. In Germany the design runs as Class 223, in Austria as ÖBB Class 2016 with the common nickname Herkules.

What the name Eurorunner reveals

The basic approach to classifying unfamiliar vehicles – shape, axle count, type of drive, number – is set out in the guide to identifying classes. Where to find the vehicle and train number in service is shown in the guide to finding the train number.

Platform design: what it means for spotters

The ER 20 is not a class in the classic sense but a platform. The difference is more than hair-splitting. A class comes out of an order placed by a railway and is tailored to that railway’s network. A platform comes out of a product decision by the manufacturer: a basic vehicle is developed and then adapted for different countries, approvals and customers.

This leads to three things you’ll come across in the field:

• The same locomotive carries different numbers. In Germany it runs as Class 223, in Austria as Class 2016. That’s not a mix-up but the result of different national registers.
• Equipment differs. Train protection, radio and approvals depend on the country of operation. Two externally identical machines can therefore have completely different areas of operation.
• The type name outlives the keeper. Service contracts expire, locomotives change operator, liveries get renewed. The platform designation stays.

For documentation, that means: note the type and the number, and treat keeper, livery and area of operation as a dated snapshot. If you only record the type, you lose the ability to follow a particular machine over the years later on – and that’s exactly what makes collecting platform vehicles interesting.

Its place in railway operations

The Eurorunner covers a field that otherwise falls between two stools: fast duties without overhead wires, arising in both freight and passenger services. In German passenger services, the design is best known from alex (Arriva-Länderbahn-Express). Behind this brand stands the group Netinera.

Field of operation	Chance of a sighting	Why
Regional services on diesel lines	medium to high	Depends on the respective operator’s service contract
Cross-border services	medium	The platform was equipped for several countries
Private railways’ freight trains	medium	The power class suits medium-weight trains
Engineering trains and special duties	low to medium	Happens, but isn’t the core business
Shunting and transfer duties	low	Centre-cab locomotives are better suited to this

In the comparison field of modern mainline diesels, you’ll find the Vossloh Eurolight as the direct rival platform, the six-axle Voith Maxima 30CC for heavier tasks and the Blue Tiger DE-AC33C as an earlier diesel-electric approach. For decades, the classic predecessor role in fast diesel services belonged to DB Class 218.

Spotting and photo tips

The ER 20 is a rewarding photographic subject because it stops at regular platforms at the head of passenger trains – unlike most freight diesels, which you only catch passing through.

• Use the platform ends. Where the train stops, you have time for a clean three-quarter view and a second shot of the data panel.
• Favour non-electrified lines. Without overhead lines the roof stays clear – and that’s exactly where the features that give away the diesel are located.
• Listen to the sound. The smoothly revving engine confirms the diesel-electric design before you can even read the number.
• Keep your distance. Platform edges, tracks and operational railway land are not photo spots. Stay behind the safety line and work with focal length rather than proximity.

A detail many people overlook: because the ER 20 is built like an electric locomotive, the classic electric-locomotive visual language works for it too. Front-on shots with a slight side angle, familiar from passenger locomotives, suit it better than the shunter perspective with a view of bonnets and walkways. If you regularly photograph freight diesels, you should deliberately rethink your usual composition for this class.

Which stations are particularly good for observation is shown in the overview of the best stations for trainspotting in Germany. Composition, exposure and panning shots are covered in the guide to good photos of trains.

Common mix-ups

Verdict

The Eurorunner is the modern answer to an old question: how do you run fast and flexibly where there are no overhead wires? Four axles, a diesel-electric three-phase drive, 140 km/h and a silhouette that deliberately looks like an electric locomotive – together they make a locomotive that works at the head of freight trains and passenger trains alike. To identify it, a look at the roof and at the number is enough.