The Siemens 5SY4204-7CC is a 2-pole SENTRON miniature circuit breaker with a C-curve trip characteristic, rated 10 kA interrupting capacity per EN 60898 at 400 V AC. It also carries a 5 kA rating under UL 1077 and CSA C22.2 No.235, so it clears faults in both IEC and North American panels — same genuine part, different passport. The breaker occupies 2 modular width units (36 mm) on a DIN rail, installable in any position, and accepts combined terminals top and bottom for daisy-chaining busbars.
What the Ratings Mean for Fit
The C-curve trips at 5–10× rated current, making it the standard choice for motor branch circuits, transformers, and lighting with moderate inrush — not for purely resistive loads (B-curve) or high-inrush welding gear (D-curve). The 10 kA breaking capacity per EN 60898 means it safely interrupts a fault current up to that level at 400 V AC; the UL 1077 5 kA rating is the North American supplementary protector limit, so in a UL 508A panel the SCCR contribution is 5 kA unless coordinated upstream. Pollution degree 3 and overvoltage category III qualify it for fixed industrial installations where conductive pollution is possible — typical in control panels near machinery. Energy limitation class 3 means it limits let-through energy to a defined level, aiding downstream component protection. The 1.3 W power loss per pole at rated current in hot state matters for thermal budgeting inside a sealed enclosure with multiple breakers side by side.
Panel Integration and Environmental Range
Snap-on DIN rail mounting with 70 mm installation depth — fits standard distribution boards and small enclosures. IP20 with connected conductors means it is protected against finger contact but not washdown; keep it inside a sealed panel. Operating temperature from -40 °C to 75 °C covers cold storage and hot machine-side cabinets. Vibration resistance per IEC 60068-2-6 — ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz — suits it for mounting on conveyor frames or machine bases without additional damping. Halogen-free and silicon-free construction matters for clean-room or semiconductor-adjacent installations where outgassing contaminates optics or coatings. Sealable allows a lead seal or lockout tag to prevent unauthorized reset — common on safety-critical or metered circuits.