Siemens SENTRON 5SL3363-6 — 63 A B-curve MCB, 3-pole, 4.5 kA
The Siemens SENTRON 5SL3363-6 is a 3-pole miniature circuit breaker rated 63 A at 400 V AC with a B tripping characteristic and a 4.5 kA breaking capacity certified to both EN 60898 and IEC 60947-2. The 4.5 kA breaking capacity at 400 V AC is the standard rating for this class under both the domestic (EN 60898) and industrial (IEC 60947-2) standards, covering most panelboard fault scenarios. Rated current is 63 A at 30 °C, derating to 59.18 A at 40 °C and 52.93 A at 55 °C — account for the thermal derating when populating a densely packed enclosure. The 10 000 mechanical switching cycles typical service life reflects a residential/infrastructure duty profile rather than a high-cycling industrial process.
Mounting position is unrestricted, and the IP20 protection class (with connected conductors) is standard for enclosed panelboard use. The sealable design allows lockout-tagout application without removing the breaker. The halogen-free and silicon-free construction avoids corrosive off-gassing in enclosed spaces — relevant for marine and HVAC applications where sensitive electronics share the enclosure. The 5SL3363-6 carries the SENTRON brand designation and is classified per IEC 81346-2 and DIN EN 61346-2 as function F (protective device). Energy limitation class 3 indicates moderate let-through energy, appropriate for downstream branch circuit protection.
No official successor or replacement has been announced. The 5SL3363-6 remains the active order code for a 3-pole, B-curve, 63 A MCB in the SENTRON 5SL6 series. If a panel was specified around a different SENTRON variant (e.g., a C-curve or lower ampacity), verify the tripping characteristic and thermal derating before substitution — the mechanical footprint and DIN-rail mounting are shared across the family.