Siemens SENTRON 5SY4204-7CC11 — 2-pole C-curve MCB, 4 A, 10 kA
The Siemens SENTRON 5SY4204-7CC11 is a 2-pole miniature circuit breaker rated 4 A with a C-curve tripping characteristic and a 10 kA breaking capacity per EN 60898. It's designed for 50/60 Hz AC systems and carries a pollution degree 3 rating, overvoltage category III — typical for industrial panel distribution in mechanical engineering and industry environments.
At 4 A rated, it's sized for a branch circuit feeding a small motor or control transformer, not a main feeder. The 2-pole configuration switches both line and neutral on a single-phase or split-phase circuit.
Temperature derating — the real-world current
Above that, derate linearly: 3.76 A at 40 °C, 3.64 A at 45 °C, 3.5 A at 50 °C, 3.37 A at 55 °C, 3.23 A at 60 °C (–). If your panel ambient runs 50 °C, plan for 3.5 A continuous load max — not the 4 A label. The operating range spans -40 °C to 75 °C (–), with humidity limits up to 95% at 55 °C, tapering to 35% at 75 °C.
Width is 36 mm (2 modular units), depth 76 mm, height 90 mm, installation depth 70 mm.