two-phase four-wire system

two-phase four-wire system

[′tü ¦fāz ′fȯr ¦wīr ′sis·təm]
(electricity)
System of alternating-current supply comprising two pairs of conductors, between one pair of which is maintained an alternating difference of potential displaced in phase by one-quarter of a period from an alternating difference of potential of the same frequency maintained between the other pair.