Four phase commuter rail power (Northeast US)
Four phase commuter rail power (Northeast US)
(OP)
Recently I was traveling in Pennsylvania, and was puzzled by the commuter train power. Above the tracks there were several circuits including what appeared to be 121 kV or 138 kV class transmission and 15 or 25 kV class distribution.
The puzzling part was that there was 4 separate conductors for the transmission. Does this configuration allow for 3 phases plus a spare for maintenance purposes? If so, is this common in any other overhead transmission applications?
The puzzling part was that there was 4 separate conductors for the transmission. Does this configuration allow for 3 phases plus a spare for maintenance purposes? If so, is this common in any other overhead transmission applications?






RE: Four phase commuter rail power (Northeast US)
RE: Four phase commuter rail power (Northeast US)
RE: Four phase commuter rail power (Northeast US)
RE: Four phase commuter rail power (Northeast US)
RE: Four phase commuter rail power (Northeast US)
AC single phase circuit feeds single phase stepdown single phase transformers that in turn feeds rectifiers to get DC for traction.
RE: Four phase commuter rail power (Northeast US)
RE: Four phase commuter rail power (Northeast US)
The picture is similar to the installation I saw. If the higher voltage has to be either transformed or rectified before being transfered to the train on the lower conductors, wouldn't 3 phase be more efficient?
RE: Four phase commuter rail power (Northeast US)