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 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. At 36 mm wide (2 modular width units) and 70 mm installation depth, it fits standard consumer units and distribution boards. The -40 °C to 75 °C operating range covers unheated plant rooms and roof spaces.
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).