This is a list of the power supply systems that are, or have been, used for railway electrification.
Note that the voltages are nominal and vary depending on load and distance from the substation.
, many trams and trains use on-board solid-state electronics to convert these supplies to run three-phase AC traction motors.
Tram electrification systems are listed here.
Key to the tables below
- Volts: voltage or volt
- Current:
- DC = direct current
- # Hz = frequency in hertz (alternating current (AC))
- AC supplies are usually single-phase (1ÃÂ) except where marked three-phase (3ÃÂ).
- Conductors:
- overhead line or
- conductor rail, usually a third rail to one side of the running rails. Conductor rail can be:
- top contact: oldest, least safe, most affected by ice, snow, rain and leaves. Protection boards are installed on most top contact systems, which increases safety and reduces these affections.
- side contact: newer, safer, less affected by ice, snow, rain and leaves
- bottom contact: newest, safest, least affected by ice, snow, rain and leaves
Systems using standard voltages
Voltages are defined by two standards: BS EN 50163 and IEC 60850.
Overhead systems
600 V DC
750 V DC
1,200 V DC
1,500 V DC
3 kV DC
AC, Hz /
AC,
AC,
Conductor rail systems
600 V DC conductor
All systems are third rail unless stated otherwise. Used by some older metros.
750 V DC conductor
Conductor rail systems have been separated into tables based on whether they are top, side or bottom contact. Used by most metros outside Asia and the former Eastern bloc.
Bottom contact
Side contact
Top contact
Mixed
1,200 V DC conductor
All systems are third rail unless stated otherwise.
1,500 V DC conductor
All systems are third rail unless stated otherwise.
Systems using non-standard voltages
Overhead systems
DC voltage
AC voltage
Three-phase AC voltage
Two wires
Three wires
Conductor rail systems (DC voltage)
Conductor rail systems have been separated into tables based on whether they are top, side or bottom contact.
Top contact systems
Side contact systems
All third rail unless otherwise stated.
Bottom contact systems
All third rail unless otherwise stated.
Conductor rail systems (AC voltage)
All systems are 3-phase unless otherwise noted.
Special or unusual types
DC, plough collection from conductors in conduit below track
DC, one ground-level conductor
DC, two-wire
DC, power from running rails
DC, four-rail
See also
Footnotes
References
External links