Digital automatic coupling
Digital automatic coupling (DAC) is a type of railway coupling developed in the 2020s to replace the English buffers and chain couplings, initially in Europe.
It resembles the Scharfenberg coupler with extra contacts to join electrical circuits (power, detection and control) and air hoses. [https://rail-research.europa.eu/news/digital-automatic-coupling-dac-the-backbone-for-full-digital-rail-freight-train-operations-in-europe/ DAC] DAC
Advantages
Function levels
{{anchor|DAC|DAC-3|DAC-4|DAC-5|DAK-3|DAK-4|DAK-5}}
Automatic couplers are categorized into five different levels in general.
- no automation
- Level 1: automated mechanic coupling (air pipes manual coupling)
- Level 2: Level 1 plus automatic coupling of air pipes (partial uncoupling with a lever)
- Level 3: Level 2 plus automatic coupling of power cables (allows uncoupling with switch)
- Level 4: Level 3 plus automatic coupling of data cables (allows uncoupling at a signal)
- Level 5: Level 4 plus remote automatic uncoupling
For the DAC the function levels are narrowed down to specific functions. The function level DAK-3 must connect the ECP brakes. The function level DAK-4 must connect the e-coupler including electric supply (400 V) and digitial sockets. The function level DAK-5 must allow for remote uncoupling using an electric motor (the DAK does not use uncoupling air pipes as defined in EN 16019 for high-speed trains). Rollout plans may use function level DAK-4 when prepared for an update to DAK-5.{{cite web|url=https://blog.railcargo.com/en/artikel/dak-faq1|title=Part I: What is Digital Automatic Coupling and what are its levels?|date=2021-01-20|publisher=Rail Cargo Group|work=DAC Question & Answer}}
Safe Remote Uncoupling
{{Anchor|Uncoupling}}
In addition to uncoupling from the driver's cab, the DAK must also enable uncoupling while moving on the shunting hump. In addition to a mechanical device using a cable pull/uncoupling lever, the demonstrator also had an electrical device with switches on a control panel attached to the side of the car. Further development should enable electrical uncoupling both from the train and from a tablet or hump computer. This is essentially software development with high safety requirements.{{cite web|url=https://www.bav.admin.ch/dam/bav/de/dokumente/verkehrstraeger/eisenbahn/gueterverkehr/konzeptbericht-dak.pdf.download.pdf/Konzeptbericht%20DAK.pdf|title=Konzeptbericht - Automatisierung im Schienengüterverkehr der Schweiz, beginnend mit der Migration zur digitalen automatischen Kupplung|date=2022-10-24|author=Wolf-Dieter Deuschle|publisher=Bundesamt für Verkehr BAV (Schweiz)}}