Siemens already sells 72.5 kV vacuum circuit breakers, both for AIS (3AV1) and GIS (8VN1) applications, up to 31.5 kA breaking current.
We are currently testing them.
Also ALSTOM (now GE) produces a 72.5 kV vacuum circuit breaker (VL109), but I don't know if it is already commercially available.
ABB has instead developed a 72.5 kV - 31.5 kA AIS, live-tank, circuit breaker (LTA 72D1) which uses CO2 as interrupting medium instead of SF6; this product is already commercially available.
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