The network uses standard gauge electric trains which in most places run on 750 V DC third rail, but the section of Line 3 running to the airport requires trains which can use overhead lines of 25 kV AC, 50 Hz.
The network uses standard gauge electric trains. These standard gauge electric trains in most places run on 750 V DC third rail. The section of Line 3 running to the airport requires trains. These trains can use overhead lines of 25 kV AC.25 kV AC is 50 Hz.