The Siemens 5SL3204-7 is a SENTRON miniature circuit breaker (MCB) — a 2-pole, C-curve device rated 4 A at 400 V AC, 50/60 Hz. It protects branch circuits in residential and light-commercial infrastructure panels against overload and short circuit, with a breaking capacity of 4.5 kA per EN 60898 and 5 kA per IEC 60947-2.
The 4.5 kA breaking capacity under EN 60898 covers the majority of domestic and light commercial fault levels in Europe; the 5 kA rating per IEC 60947-2 gives a small headroom margin for industrial sub-distribution where the prospective short-circuit current is higher. Two poles (2P) switch both line and neutral simultaneously, which is required for single-phase circuits where the neutral is not bonded to ground downstream — common in TT and IT earthing systems. Mechanical life of 10,000 operating cycles typical — adequate for most panel applications where the breaker is not used as a daily switch; if frequent switching is expected, consider a dedicated disconnect.
Mounting position any, which simplifies layout in crowded enclosures. Halogen-free and silicon-free construction — important for installations where off-gassing during a fault could damage sensitive electronics or where silicone contamination must be avoided (e.g., paint shops, clean rooms). Sealable — the breaker can be locked in the OFF position with a padlock or seal, meeting lockout/tagout requirements for maintenance isolation.