Transmission Line Circuit Isolation
Phase over Phase Switches
Independent single gap interrupters are more reliable than mechanically shared multigap interrupters
One way, two way and more phase over phase switches are used in transmission lines to isolate and segment the system. These configurations are used in restricted Right Of Way lines where a substation is too expensive.
Segmenting the system requires switches that can break loop current and drop lines. Traditionally this has been done by switches sharing a single multi gap vacuum interrupter and/or whip. These highly mechanical designs have been unreliable and cause of multiple outages, require excessive maintenance and experience a high number of SAIDI, SAIFI minutes.
Many utilities have switched to independent single gap SF6 interrupters for this application. These multiple way switches are simpler to install and adjust, significantly improving the operational reliability.
Watch our installation video for the ES-1 Phase over phase switch: http://www.youtube.com/watch?v=EfwLFSlAEvY