The Siemens SENTRON 5SL4204-7 is a 2-pole miniature circuit breaker rated 4 A with a C tripping characteristic, designed for 400 V AC systems at 50/60 Hz. Its 10 kA breaking capacity is certified to both EN 60898 and IEC 60947-2, meaning it clears fault currents up to 10 kA without welding its contacts or cascading failure upstream — that's the figure that governs coordination with the upstream protective device in a distribution board.
Occupies 2 modular width units (36 mm) on a DIN rail, with a depth of 76 mm and an installation depth of 70 mm. Snap-on mounting in any position — no derating for upside-down or sideways installs.
C-curve trips at 5–10× rated current (20–40 A magnetic trip), so it's sized for moderate inrush loads like small motor starters, lighting banks, and transformer primaries — not for purely resistive loads (B-curve) or high-inrush drives (D-curve). The 4 A rating at 400 V AC gives 2.7 kVA per pole at unity power factor. Power loss per pole is 1.2 W in hot operating state; two poles dissipate 2.4 W total — negligible in a ventilated enclosure but worth noting if the breaker is sealed in a non-ventilated sub-panel.
Compliance and environment
Halogen-free and silicon-free construction. Sealable for lockout/tagout.