Information about the Luas track and power supply
The Luas track gauge is 1,435mm and is the same on both lines. Ri59N grooved rail is used in most street-running sections and at stops whilst S49 rail is used in off-street areas. There are also some sections of Ri60N rail. The minimum track radius is 25 metres on running lines.
Street-running sections shared by Luas, road traffic and pedestrian traffic have a variety of surface finishes including asphalt, granite sets and imprinted concrete. Through all stops the track is surfaced with imprinted concrete. Most off-street sections of the system are either traditional or ballasted track with the exception of short sections of grassed track. Ballast track is utilised extensively on the Green Line and at the depots.
The power supply for Luas is delivered from electrical sub-stations at 750 volts DC via an Overhead Catenary System (OCS). The OCS is supported by poles or anchored to buildings adjacent to the railway. The 750 volt DC supplied to the trams is converted to AC current to power three motorised bogies on each tram. The circuit is then completed by the running rails providing a path for the return current.
Power is supplied to the sub-stations from the national grid at 10 kV AC. There are 20 traction supply sub-stations in the system, seven of which are underground.