Siemens SENTRON 5SY5404-7 — 4-pole C-curve MCB, 4 A, 10 kA, 880 VDC
The Siemens SENTRON 5SY5404-7 is a 4-pole miniature circuit breaker with C-curve tripping characteristic, rated 4 A at 35 °C and breaking 10 kA per EN 60898. It carries an 880 VDC rating per EN 60898-2, making it suitable for DC circuits up to that voltage. The universal-current design (AC/DC) and pollution degree 2 rating fit standard commercial and industrial panel environments.
The C-curve (tripping characteristic class C) means the breaker holds up to 5–10× rated current for short durations, so it tolerates motor inrush and capacitive loads without nuisance tripping — common for general-purpose distribution and mixed loads. At 35 °C the breaker is rated 4 A; at 40 °C it derates to 3.76 A, at 50 °C to 3.5 A, and at 60 °C to 3.22 A. EN 60898 is the standard for household and similar installations; for industrial panels with higher prospective fault current, verify coordination with the upstream device. Rated 880 VDC, this 4-pole breaker can be used in DC circuits — for example, in photovoltaic combiner boxes or DC bus distribution — as long as the polarity is observed (AC as required, observe DC polarity per the evidence). The 4-pole configuration (4P) switches all four poles simultaneously, giving full isolation on three-phase plus neutral or on a 4-wire DC system.
Touch protection is built in — no exposed live parts when wired.