Siemens 3VA1340-4EF42-0AA0 circuit breaker 3VA1 IEC frame 400 breaking capacity class S Icu=36kA @ 415V 4-pole, line protection TM240, ATAM, In=400A overload protection Ir=280A...400A short-circuit protection Ii=5...10 x In N conductor unprotected nut kee