What this RCBO covers
The Siemens 5SU1324-7FA32 is a 2-pole RCBO (residual current circuit breaker with overcurrent protection) from the SENTRON family. It combines a 32 A thermal-magnetic overcurrent trip (C-curve) with a 30 mA type A residual-current detection block in a single 3-module-width (54 mm) package. The C-curve means the magnetic trip operates at 5 to 10 times rated current — standard for mixed resistive and moderate inductive loads like lighting circuits, small motor starters, or socket-outlet groups in commercial and residential panels. The 30 mA residual sensitivity covers basic shock protection for personnel.
Breaking capacity and coordination
Rated breaking capacity is 10 kA per EN 60898 (the residential-branch standard) and 15 kA per IEC 60947-2 (the industrial-standard rating). The higher IEC figure matters when this RCBO sits downstream of a transformer with higher prospective fault current — it gives the panel designer 15 kA SCCR headroom at 230/240 V AC. The 1 kA surge-current withstand (8/20 μs waveform) is the impulse-sparkover rating; it means the device survives typical lightning-induced transients without nuisance tripping or internal damage.
Panel fit and environment
Dimensions are 90 mm high, 54 mm wide (3 modular units), 77 mm deep, with a 70 mm installation depth. That 77 mm depth is the body-only; the 70 mm installation depth is what matters for enclosure selection — it fits standard 80 mm-deep distribution boards. Mounting position is any orientation, and supply can enter from top or bottom, which simplifies wiring in tight gland-plate layouts. IP20 rating applies only with the distribution board installed and conductors connected — not a standalone IP rating for open-panel use. Halogen-free and silicon-free construction matters for clean-room or high-reliability environments where outgassing can contaminate contacts or optics.