3kVDC

This is a list of the power supply systems that are, or have been, used for tramway and railway electrification systems.

Note that the voltages are nominal and vary depending on load and distance from the substation.

Many modern trams and trains use on-board solid-state electronics to convert these supplies to run three-phase AC induction motors.

Voltages are defined by two standards: BS EN 50163 and IEC 60850.

This voltage is mostly used by older tram systems worldwide but by a few new ones as well.

This voltage is used for most modern tram systems.

Metrô-SP

São Paulo

Lines 1, 2, 3 and 15 (monorail), 17 (future, monorail)

While 25 kV 60 Hz is not standardized by BS EN 50163 and IEC 60850; it is the logical equivalent of 25 kV 50 Hz in countries where 60 Hz is the normal grid power frequency.

All third rail unless stated otherwise.
Used by most older US subways.

Conductor rail systems have been separated into tables based on whether they are top, side or bottom contact. All systems are third rail unless stated otherwise.

Downtown Line operated by SBS Transit
Thomson-East Coast Line

Conductor rail systems have been separated into tables based on whether they are top, side or bottom contact.

1904, revenue service 1906–1908

150 V is used in station areas to limit train speed

To enable London Underground trains to operate between Queens Park and Harrow & Wealdstone. Similar bonding arrangements are used on the North London Line between Richmond and Gunnersbury and South West Trains Putney Bridge to Wimbledon.

variable voltage between 10 kV and 14 kV and frequency between 38 Hz and 48 Hz.

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