The Siemens 5SY4305-7CC is a SENTRON miniature circuit breaker (MCB) rated 0.5 A with a C tripping characteristic, 3-pole, for 400 V AC systems. Rated 0.5 A at 400 V AC, this 3-pole MCB occupies 3 width units (54 mm) on a DIN rail. Terminal capacity accepts solid or stranded conductors from 0.75 mm² up to 35 mm², with a tightening torque of 2.5 to 3.5 N·m.
Breaking capacity and approvals
Breaking capacity is 10 kA at 400 V AC per EN 60898, and 5 kA per UL 1077 and CSA C22.2 No. 235. The UL/CSA rating is lower — that is typical for the standard, not a limitation of the design. If the panel requires UL 489 listing, this part is not the right fit; it is a supplementary protector under UL 1077. Overvoltage category III and energy limiting class 3 apply.