dual-voltage

Able to run using two different voltages, depending on the voltage supplied to the particular railway line, whether by third rail direct current or overhead wires.

With multi-voltage techniques in their present state of development, the greatest disadvantage resulting from these differences is the impossibility of fast through multiple-unit expresses. Dual-voltage trains work between Amsterdam and Brussels, but many additional problems would arise if they were to run south of Luxembourg.

Transport for London has ordered 48x4-car and 6x5-car '710s' from Bombardier, with the initial order of 45x4-car units comprising 31x4-car AC-only units for West Anglia services and 14x4-car dual-voltage units for the Gospel Oak to Barking line (GOBLIN) and Watford DC services. However, this has recently been varied, with one of the AC-only units now to be delivered as a dual-voltage set. The nine units later added to the order are all dual-voltage, meaning the total order is now for 30x4-car AC-only units and 18x4-car and 6x5-car dual-voltage units.

Provided with two separate traction power supplies at different voltages, typically as a changeover point between voltages.

Quévy, the end-to-end junction with the S.N.C.F. main line via Aulnoye to Paris, will be a dual-voltage station with arrangements of overhead and signalling equipment similar to those at Luxembourg, another junction between the 3,000V and 25kV systems.