What it is and what it does
The Siemens SENTRON 5SU9304-7KX06 is an RCD-operated circuit breaker — an RCBO — combining overcurrent protection and residual current detection in a single 18 mm wide module. It protects a single-phase final subcircuit (1P+N, 2 poles) with a rated current of 6 A at 30 °C and a C tripping characteristic, meaning it handles moderate inrush from motor or lighting loads without nuisance trips. The breaking capacity is 10 kA per both EN 60898 and IEC 60947-2, so it safely interrupts fault currents up to that level in a 110/120 V AC circuit.
Key ratings and what they mean for fit
The 6 A rating at 30 °C derates to 5.7 A at 40 °C and 5.16 A at 55 °C — if the panel ambient runs hot, the continuous load must stay under the derated figure. The C-curve trips at 5–10× rated current, so it suits mixed resistive-inductive loads like small pumps or control transformers. The 10 kA SCCR per IEC 60947-2 is the maximum prospective fault current the device can interrupt without failing; verify the available fault current at the installation point stays below that.
Panel integration and environment
This RCBO occupies one modular width unit (18 mm) on a DIN rail, with a depth of 77 mm and an installation depth of 70 mm. It mounts in any position, which helps when filling a crowded enclosure. The IP20 rating applies to the device alone; with the distribution board installed and conductors connected, IP40 is achieved. The operating temperature range is -40 °C to 75 °C, and it withstands up to 95% humidity. Pollution degree 2 and overvoltage category III are standard for residential and commercial panel environments.