Siemens 3VA1450-4EF42-0AA0 circuit breaker 3VA1 IEC Frame 630 breaking capacity class S Icu=36 kA @ 415 V 4-pole, line protection TM240, ATAM, In=500 A overload protection Ir=350 A...500 A short-circuit protection Ii=5...10 x In N conductor unprotected nu