This standard applies to all ac high-voltage generator circuit breakers rated on a symmetrical current basis that are installed between the generator and the transformer terminals. Pumped storage installations are considered a special application@ and their requirements are not completely covered by this standard.NOTE ?? Since no other national or international standard on generator circuit breakers exists@ this standard is used worldwide. The revision of IEEE Std C37.013-1993 takes care of this fact by adapting its content in some places to international practice.