Vacuum Circuit Breakers 2 : Circuit breakers, normally applied at medium voltages, that use vacuum interrupters to extinguish the electrical arc and shut-off flowing current
Young & Company Electric Power Products and Related Engineering Services, Glossary of Electrical Terms, http://www.youngco.com/young2.asp?ID=4&Type=3, CA., USA 2001. (Electr Sfty - Amer) {514}