The Siemens 5SY4504-6 is a 1P+N miniature circuit breaker from the SENTRON family, tripping characteristic B, rated 10 kA breaking capacity under IEC/EN 60898-1 and 35 kA under IEC 60947-2. The 1P+N configuration switches both phase and neutral, with the neutral pole switching but not protecting — it opens the neutral when the phase trips. This is common in single-phase final subcircuits where disconnecting the neutral is required by local wiring rules. The neutral conductor switching is built in, so no separate neutral link is needed. Rated operating voltage is 230 V AC, with a maximum of 250 V in single-phase operation. Frequency is 50/60 Hz.
Width is 36 mm (2 modular units). Combined terminal at top and bottom — accepts both busbar and cable in the same clamp. Sealable (tamper-evident cover can be locked). Installable supplementary devices (auxiliary contacts, shunt trip, undervoltage release) can be added on the side.
For a maintenance spares purchaser, keeping one in the cabinet before it fails is straightforward — this is a part you can buy ahead on without worrying about a short production window.
Designed to IEC/EN 60898-1 (domestic MCB standard) and IEC/EN 60947-2 / UL1077 (industrial supplementary protector standard). Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz. Mechanical service life 10,000 operating cycles typical. The dual-standard compliance means it can be used in both residential distribution boards and industrial control panels, but the UL1077 listing is as a supplementary protector — not a branch-circuit rated breaker per UL 489.