What the ratings mean for fit
The Siemens 5SL3232-6 is a 2-pole miniature circuit breaker from the SENTRON 5SL family, rated 32 A at 400 V AC with a B-curve tripping characteristic. The B-curve means it trips magnetically at 3 to 5 times rated current — suited for resistive and lighting loads where inrush is modest, not for motor starting. The 4.5 kA breaking capacity (per EN 60898 and IEC 60947-2) tells you the maximum fault current it can safely interrupt at 400 V; match this to your prospective short-circuit current at the panelboard. Two-pole construction (2P) switches both phase and neutral, with no neutral conductor switching internally — it breaks both poles, so it's for single-phase circuits where you want full isolation. Snap it onto a DIN rail in any mounting position. At 36 mm wide (2 modular width units) and 70 mm installation depth, it fits standard consumer units and distribution boards. IP20 with connected conductors means it's for dry indoor enclosures — not for washdown or outdoor exposure. The -40 °C to 75 °C operating range covers unheated plant rooms and roof spaces.
How it compares to the 5SL3120-6MB
The 5SL3120-6MB is the same 2-pole B-curve 5SL frame but rated 20 A instead of 32 A. Physically identical footprint — same 36 mm width, same DIN-rail clip, same 70 mm installation depth. If your panel was wired for a 20 A circuit and you need to upsize to 32 A, the 5SL3232-6 drops straight in without rewiring the busbar or enclosure. The only difference is the thermal-magnetic calibration; swap them one-for-one if the load current allows.
Integration notes
Sealable (padlockable toggle) for lockout/tagout — the switch can be locked in the off position. Halogen-free and silicon-free construction for environments sensitive to outgassing (clean rooms, medical, or data center panels). Degree of pollution 2 and overvoltage category III suit fixed-installation distribution boards. Energy limitation class 3 means it limits let-through energy under fault conditions, which helps with downstream coordination.